Organic Chemistry - Arihant Prakashan- Book Information and Review

I read the first five chapters so far. It is good material.

R.C. Mukherjee, Modern Approach to Chemical Calculations Book Information and Review

For problems in Physical Chemistry

Physical chemistry- Study Guide - IIT JEE

Text books

NCERT XI and XII

Jauhar

Arihant Prakashan

R.C. Mukherjee, Modern Approach to Chemical Calculations

Physical Chemistry - General topics- Study Guide - IIT JEE

The concept of atoms and molecules; Dalton's atomic theory;

Mole concept; Chemical formulae; Balanced chemical equations; Calculations (based on mole concept) involving common oxidation-reduction, neutralisation, and displacement reactions;

Concentration in terms of mole fraction, molarity, molality and normality.

Gaseous and Liquid states- Study Guide - IIT JEE

Absolute scale of temperature, ideal gas equation; Deviation from ideality, van der Waals equation; Kinetic theory of gases, average, root mean square and most probable velocities and their relation with temperature;

Law of partial pressures; Vapour pressure; Diffusion of gases.

Atomic structure and chemical bonding- Study Guide - IIT JEE

Bohr model, spectrum of hydrogen atom, quantum numbers; Wave-particle duality, de Broglie hypothesis; Uncertainty principle; Quantum mechanical picture of hydrogen atom (qualitative treatment), shapes of s, p and d orbitals; Electronic configurations of elements (up to atomic number 36); Aufbau principle; Pauli's exclusion principle and Hund's rule;

Orbital overlap and covalent bond; Hybridisation involving s, p and d orbitals only; Orbital energy diagrams for homonuclear diatomic species; Hydrogen bond; Polarity in molecules, dipole moment (qualitative aspects only); VSEPR model and shapes of molecules (linear, angular, triangular, square planar, pyramidal, square pyramidal, trigonal bipyramidal, tetrahedral and octahedral).





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Energetics- Study Guide - IIT JEE

First law of thermodynamics; Internal energy, work and heat, pressure-volume work; Enthalpy, Hess's law; Heat of reaction, fusion and vapourization; Second law of thermodynamics; Entropy; Free energy; Criterion of spontaneity.

Chemical equilibrium- Study Guide - IIT JEE

Law of mass action; Equilibrium constant, Le Chatelier's principle (effect of concentration, temperature and pressure); Significance of DG and DGo in chemical equilibrium;

Solubility product, common ion effect, pH and buffer solutions; Acids and bases (Bronsted and Lewis concepts); Hydrolysis of salts.

Electrochemistry- Study Guide - IIT JEE

Electrochemical cells and cell reactions; Electrode potentials; Nernst equation and its relation to DG; Electrochemical series, emf of galvanic cells; Faraday's laws of electrolysis; Electrolytic conductance, specific, equivalent and molar conductance, Kohlrausch's law; Concentration cells.

Chemical Kinetics- Study Guide - IIT JEE

Rates of chemical reactions; Order of reactions; Rate constant; First order reactions; Temperature dependence of rate constant (Arrhenius equation).

Solid State- Study Guide - IIT JEE

Classification of solids, crystalline state, seven crystal systems (cell parameters a, b, c, a, b, g), close packed structure of solids (cubic), packing in fcc, bcc and hcp lattices; Nearest neighbours, ionic radii, simple ionic compounds, point defects.

Solutions- Study Guide - IIT JEE

Raoult's law;
Molecular weight determination from lowering of vapor pressure, elevation of boiling point and depression of freezing point.

Surface chemistry- Study Guide - IIT JEE

Elementary concepts of adsorption (excluding adsorption isotherms); Colloids: types, methods of preparation and general properties; Elementary ideas of emulsions, surfactants and micelles (only definitions and examples).

Nuclear Chemistry- Study Guide - IIT JEE

Radioactivity: isotopes and isobars; Properties of a, b and g rays; Kinetics of radioactive decay (decay series excluded), carbon dating; Stability of nuclei with respect to proton-neutron ratio; Brief discussion on fission and fusion reactions.

Inorganic Chemistry - Study Guide - IIT JEE

Textbooks

NCERT Books for XI and XII

Jauhar for XI and XII

Arihant Prakashan

Inorganic Chemistry for Competitions by O P Tandon, G.R. Bathla & Sons, Meerut

Preparation and Properties of Compounds of Metals- Study Guide - IIT JEE

Preparation and properties of the following compounds: Oxides, peroxides, hydroxides, carbonates, bicarbonates, chlorides and sulphates of
sodium,
potassium,
magnesium and
calcium;

compounds of Aluminium: alumina, aluminium chloride and alums;

Preparation and Properties of Non-Metals- Study Guide - IIT JEE

Isolation/preparation and properties of the following non-metals: Boron, silicon, nitrogen, phosphorus, oxygen, sulphur and halogens; Properties of allotropes of carbon (only diamond and graphite), phosphorus and sulphur.

Preparation and Properties of Compounds of Nonmetals

Boron: diborane, boric acid and borax;
Carbon: oxides and oxyacid (carbonic acid);
Silicon: silicones, silicates and silicon carbide;
Nitrogen: oxides, oxyacids and ammonia;
Phosphorus: oxides, oxyacids (phosphorus acid, phosphoric acid) and phosphine; Oxygen: ozone and hydrogen peroxide;
Sulphur: hydrogen sulphide, oxides, sulphurous acid, sulphuric acid and sodium thiosulphate;

Halogens and Halogen Compounds- Study Guide - IIT JEE

Isolation/preparation and properties of halogens

Halogen compounds: hydrohalic acids, oxides and oxyacids of chlorine, bleaching powder; Xenon fluorides;

Fertilizers- Study Guide - IIT JEE

commercially available (common) NPK type.

Transition elements (3d series): - Study Guide - IIT JEE

Definition, general characteristics, oxidation states and their stabilities, colour (excluding the details of electronic transitions) and calculation of spin-only magnetic moment; Coordination compounds: nomenclature of mononuclear coordination compounds, cis-trans and ionisation isomerisms, hybridization and geometries of mononuclear coordination compounds (linear, tetrahedral, square planar and octahedral).

Ores and minerals- Study Guide - IIT JEE

Commonly occurring ores and minerals of
iron,
copper,
tin,
lead,
magnesium,
aluminium,
zinc and
silver

Extractive metallurgy- Study Guide - IIT JEE

Chemical principles and reactions only (industrial details excluded);
Carbon reduction method (iron and tin);
Self reduction method (copper and lead);
Electrolytic reduction method (magnesium and aluminium);
Cyanide process (silver and gold).

Principles of qualitative analysis- Study Guide - IIT JEE

Inorganic Chemistry

Groups I to V (only Ag+, Hg2+, Cu2+, Pb2+, Bi3+, Fe3+, Cr3+, Al3+, Ca2+, Ba2+, Zn2+, Mn2+ and Mg2+); Nitrate, halides (excluding fluoride), sulphate, sulphide and sulphite.

Organic Chemistry - Study Guide - IIT JEE

Recommended books

NCERT
Arihant Prakashan
Jauhar

Many recommend
Morrison and Boyd

Organic Chemistry Concepts - General Organic Chemistry - - Study Guide - IIT JEE

Hybridisation of carbon; Sigma and pi-bonds; Shapes of molecules;

Structural and geometrical isomerism; Optical isomerism of compounds containing up to two asymmetric centers, (R,S and E,Z nomenclature excluded);

Conformations of ethane and butane (Newman projections);

IUPAC nomenclature of simple organic compounds (only hydrocarbons, mono-functional and bi-functional compounds);



Resonance and hyperconjugation; Keto-enol tautomerism;

Determination of empirical and molecular formula of simple compounds (only combustion method);

Hydrogen bonds: definition and their effects on physical properties of alcohols and carboxylic acids;

Inductive and resonance effects on acidity and basicity of organic acids and bases;

Polarity and inductive effects in alkyl halides;

Reactive intermediates produced during homolytic and heterolytic bond cleavage; Formation, structure and stability of carbocations, carbanions and free radicals.

Alkanes- Study Guide - IIT JEE

Preparation, properties and reactions of alkanes: Homologous series, physical properties of alkanes (melting points, boiling points and density); Combustion and halogenation of alkanes; Preparation of alkanes by Wurtz reaction and decarboxylation reactions.

Alkenes- Study Guide - IIT JEE

Preparation, properties and reactions of alkenes: Physical properties of alkenes (boiling points, density and dipole moments); Acid catalysed hydration of alkenes (excluding the stereochemistry of addition and elimination); Reactions of alkenes with KMnO4 and ozone; Reduction of alkenes; Preparation of alkenes by elimination reactions; Electrophilic addition reactions of alkenes with X2, HX, HOX and H2O (X=halogen); Metal acetylides.

Alkynes- Study Guide - IIT JEE

Preparation, properties and reactions of alkynes:
Physical properties of alkynes (boiling points, density and dipole moments); Acidity of alkynes; Acid catalysed hydration of alkynes (excluding the stereochemistry of addition and elimination); Reduction of alkynes; Preparation of alkynes by elimination reactions; Addition reactions of alkynes; Metal acetylides.

Benzene- Study Guide - IIT JEE

Preparation, properties and reactions

Reactions of benzene: Structure and aromaticity; Electrophilic substitution reactions: halogenation, nitration, sulphonation, Friedel-Crafts alkylation and acylation; Effect of o-, m- and p-directing groups in monosubstituted benzenes.

Alkyl halides- Study Guide - IIT JEE

Preparation, properties and reactions

Characteristic reactions of

rearrangement reactions of alkyl carbocation, Grignard reactions, nucleophilic substitution reactions;

Haloarenes- Study Guide - IIT JEE

Preparation, properties and reactions
Characteristic reactions of

Haloarenes: nucleophilic aromatic substitution in haloarenes and substituted haloarenes - (excluding Benzyne mechanism and Cine substitution).

Alcohols- Study Guide - IIT JEE

Preparation, properties and reactions

Characteristic reactions of Alcohols

esterification, dehydration and oxidation, reaction with sodium, phosphorus halides, ZnCl2/conc.-HCl, conversion of alcohols into aldehydes and ketones;

Phenols - - Study Guide - IIT JEE

Preparation, properties and reactions

Characteristic reactions of

Acidity, electrophilic substitution reactions (halogenation, nitration and sulphonation); Reimer-Tieman reaction, Kolbe reaction.

Aldehydes and Ketones- Study Guide - IIT JEE

Preparation, properties and reactions

Characteristic reactions of
oxidation, reduction, oxime and hydrazone formation; aldol condensation, Perkin reaction; Cannizzaro reaction; haloform reaction and nucleophilic addition reactions (Grignard addition);


NCERT Text Book for Class XII Part II, Chapter 12

12.1 Nomenclature and Structure of Carbonyl Group
12.2 Preparation of Aldehydes and Ketones
12.3 Physical properties
12.4 Chemical Reactions
12.4.1 Nucleophilic addition reactions
12.4.2 Reduction
12.4.3 Oxidation
12.4.4 Reactions due to α-hydrogen
Aldol condensation
12.4.5 Other reactions
12.4.5(i) Cannizzaro reaction
12.4.5(ii) electrophilic substitution reaction
12.5 Uses of Aldehydes and Ketones

Carboxylic Acids- Study Guide - IIT JEE

Preparation, properties and reactions

Characteristic reactions of
formation of esters, acid chlorides and amides, ester hydrolysis;

Amines- Study Guide - IIT JEE

Preparation, properties and reactions

Characteristic reactions of Amines

basicity of substituted anilines and aliphatic amines, preparation from nitro compounds, reaction with nitrous acid, azo coupling reaction of diazonium salts of aromatic amines, Sandmeyer and related reactions of diazonium salts; carbylamine reaction

Carbohydrates- Study Guide - IIT JEE

Classification; mono and di-saccharides (glucose and sucrose); Oxidation, reduction, glycoside formation and hydrolysis of sucrose.

Amino acids and peptides - Study Guide - IIT JEE

General structure (only primary structure for peptides) and physical properties.

Properties and uses of some important polymers - Study Guide IIT JEE

Natural rubber, cellulose, nylon, teflon and PVC.

Practical Organic Chemistry - Study Guide for IIT JEE

Detection of elements (N, S, halogens); Detection and identification of the following functional groups: hydroxyl (alcoholic and phenolic), carbonyl (aldehyde and ketone), carboxyl, amino and nitro; Chemical methods of separation of mono-functional organic compounds from binary mixtures.

General Organic Chemistry

The chapters that deal with concepts applicable to all the organic compounds may be grouped under the head General Organic Chemistry. Six posts follow this chapter to cover various concepts applicable to all the compounds. All the posts are revision points only. The detailed reading of the material has to be done from the text books.

Concept of Acids and Bases - Application to Organic Compounds

Bronsted-Lowry theory

Acid is a proton donor and based is proton acceptor.
Any compound that has a hydrogen atom can act as a Bronsted-Lowry acid.
Hence H-A is used as general representation for an acid (H represents hydrogen)

Lewis Theory
According to Lewis theory, any molecule that has an electron deficient atom (site) that can accept a pair of electrons, is an acid.

Conjugate acid

Conjugate base

Acidity constant

Ph value

The effects of structure of the molecule on the strengths of acids and bases

Acids and Bases - Videos on Knol

Bonding Concepts - Organic Compounds

Valency

Electronegativity
polarity
Dipole momennt

Atomic orbitals
Molecular orbitals

Hybridisation

Resonance

Elemental Analysis of Organic Compounds - Quantitative and Qualitative

Revision points

Qualitative analysis

Functional group identification

Carboxylic group - sodium bicarbonate test
Alcoholic group - Ceric ammonium nitrate
Phenolic group - Neutral ferric chloride solution

Carbonyl compounds - Brady's test
Aldehyde group - Tollen's reagent (silver-mirror test)
Methyl ketones - Iodoform test

Ester - Hydroxyl amine
Ester - saponification

Amides - nitrous acid test

Alkenes and Alkynes - Bromine test, Baeyer's test

Quantitative analysis

Nomenclature of organic Compounds

IUPAC Rules for Nomenclature of Organic Compounds

IUPAC Rules for Nomenclature of Alkanes

1. The unbranched alkanes are named according to the number of alkanes of carbons. Examples: Methane, Ethane, Propane etc.

2. For alkanes containing branched carbon chains, the principal chain of the compound needs to be determined. This is the longest continuous carbon chain in the molecule.

3. In determining the principal chain sometimes, two or more chains in the molecule may have same number of carbons in their chains. In such a case, the chain having the greater number of branches is chosen as the principal chain of the molecule.

4. Numbers have to be given for the carbon atoms, to which the branches are attached. To give numbers, principal chain of the carbon atoms is numbered from the direction that gives the lower number to the first branching point.

5. Branching groups are in general termed as substituents. Each group is to be given an IUPAC name (prefix name) and is prefixed to the name of the principal chain of the molecule.

6. Compound is named according to the pattern “number- alkyl group prefix name principal chain name”. Name of the group (prefix) and name of the principal chain are written together as one word.

7. Where there are more than one substituent groups, each substituent group must be given its own number depending on the carbon to which it was attached.

8. In case of identical substituents, prefixes di, tri, tetra etc., are used before the group prefix name to indicate number of identical groups.

9. Substituent groups are written in alphabetical order regardless of their location in the principal chain but the prefixes di, tri… as well as the prefixes tert- and sec- are ignored in deciding the alphabetical order, and the prefixes iso, neo, and cyclo are considered.

10. If the number of carbon atoms of the principal chain from either gives identical numbers to the substituent attachment carbons, the direction which gives the lower number to the first written group (according to the alphabetical order) is chosen.

Isomerism

Major Topics

Structural isomerism

Stereo isomerism

Structural isomerism is further classifed as

Chain or Nuclear Isomerism
Functional isomerism
Metamerism
Tautomerism

Sterio isomerism is further classfied as

Geometrical isomerism
Optical isomerism, enantiomerism or d,l isomerism

Geometrical isomerism - E and Z configuration

Optical isomerism has the follwing concenpts

Diastereomer
erthroenantiomers
Threoenantiomers
Meso compound
Racemic mixture
R and S configuration

Conformations

Organic Reaction Mechanisms

An organic reaction occurs between a substratum (an organic compound) and an attacking agent termed a reagent.

1. Bond Cleavage (Homolytic or Heterolytic Cleavage)

The bonds in the organic compound break and reaction intermediates are formed. These reactions intermediates are:

1. Free radicals
2. Carbocations (An ion that has carbon atom with positive charge)
3. Carbanion (An ion with carbon atom with negative charge)
4. Carbene (singlet and triplet)
5. Radical ion

Homolytic Fission

Free radicals form as intermediates

Heterolytic Fission

Carbocations, carbanions and carbenes form during this type of fission

2. Reagents

Electrophiles, Nucleophiles and Ambiphiles are reagents.

Electrophiles:
This reagent requires electrons.
Examples: ions like NO2+, Cl+
and atoms in molecules like S03 and BF3.

Nucleophiles

They are negatively charged and attack positively charged atoms.
Examples ions like OH-, CN-, H- or
atoms in molecules like N in NH3 and O in H2O.

Ambiphiles

H2O It has an electron attacking and electron repelling site also.



3. Inductive Effect:
The study of this effect is important because of its implication for the stability of reaction intermediates.

When an electron-withdrawing or electron-releasing group (substituent) is attached to carbon chain, polarity is induced on the carbon atom and on the substituent attached to it. This is called inductive effect or simply as I-effect.

Negative Inductive Effect (_-I Effect)
Postive Inductive Effect (₊I Effect)


4.Electromeric effect
In presence of an electrophile, there is complete transfer of π electrons from one atom to other to produce temporary polarity on atoms joined by mutliple bonds. It is called electromeric effect.

Positive Electromeric effect
Negative Electromeric effect

5. Mesomeric effect

In conjugate systems (compounds having alternate π and sigma bonds) π-electron shifting takes place consecutively giving permanent polarity on the chain. This π-electron shift in conjugate systems is called mesomeric effect or conjugate effect.

Positive
Negative

6. Hyperconjugation

When an alkyl group is attached to a double bond (unsaturated system in general), the hydrogen in the alkyl group releases an electron and becomes positive. And in the process there is no bond formation between C and H⁺. This type of electron release is called hyperconjugation.

7. Types of Reactions

Addition
Elimination
Substitution
Rearrangement

7a. Addition Reactions
This reaction is characteristic of the compounds having double or triple bonds.

7b. Elimination Reactions

In most elimination reactions, two groups on adjacent atoms are lost and a double bond is formed. Thus, the product of an eliminatin reaction is an alkene.

7c. Substitution Reactions

In this reaction, one atom or group of atoms in a molecule is replaced by another.





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Alkenes - Revision Facilitator

Alkenes Introduction

Nomenclature

Isomerism

Methods of Preparation

Partial reduction of alkynes

Dehydrohalogenation of alkyl halides.

Dehalogenation of vicinal dihalides (dihalogen compounds)

Dehydration of alcohols

Kolbe's electrolytic method (alkenes from salts dicarboxylic acids)

Preparation of alkenes by elimination reactions

Alkenes - Physical properties

1. State

2. Melting points

3. Boiling points

4. Dipole moments

5. Solubility


Alekenes Chemical Properties

Electrophilic addition reactions

Halogen acids
Water
Hypohalous acid
Sulphuric acid

oxidation,

Combustion
Hydroboration oxidation
Potassium permanganate - cold and hot
Catalytic oxidation
Reaction with Ozone

Reduction

Polymerisation
of ethene
of vinyl chloride
of styrene
of tetrafluoroethylene



Replacement reactions.

Addition of sulphuric acid

Acidity of alkenes

Acid catalysed hydration of alkenes

Reactions of alkenes with KMnO4

Reactions of Alkenes with Ozone

Reduction of Alkenes

Coordination Compounds - Revision Facilitator

Try to recollect relevant points on the topic and if required right click on the topic if link is given and open in a new window to read the relevant material. Close the window and come back.


1. Werner's Coordination Theory

2. Coordination Compounds - Important Terms

3. Nomenclature of Coordination Compounds

4. Isomerism in Coordination Compounds

5. Bonding in Coordination Compounds

6. Bonding in Metal Carbonyls

7. Stability of Coordination Compounds

8. Importance and Applications of Coordination Compounds

Coordination Compounds - Important Terms - Revision Points

Coordination compounds: coordination compounds are a special class of compounds in which the central atom is surrounded by ions and atoms beyond their normal valency


OR

Coordination or complex compounds may be defined as a molecular compound that results from the combination of two or more simple stable molecular compounds and retains its identity in the solid as well as in the dissolved state .The properties of such compounds are totally different than individual constituents. A coordination compound contains very often but not always a complex ion.


Complex ion
An electrically charged species which consists of a central metal ion or atom surrounded by a group of ions or neutral molecules(it may be noted that a complex may be positively charged or negatively charged or neutral).
Types of complex:
1.cationic complex
2.anionic complex
3.neutral complex
cationic complex :A complex which has net positive charge .
anionic complex : A complex which has net negative charge .
neutral complex: A complex which has no net charge or simply neutral.


TERMINOLOGY OF COORDINATION COMPOUNDS:




1 .Ligands:
The neutral molecule or ions which are directly attached to the central metal ion or atom through coordinate bonds in the complex ion is called Ligand.
>Ligands should have lone pair of electrons
>Ligands donate the lone pair to the central metal atom or ion forming coordinate covalent bond .
>thus Ligand are Lewis bases and central metal ion is a Lewis acid.

Types of ligands:
1. monodentate or unidentate ligands :ligand having only one donor atom.
2.bidentate ligand :ligand having two donor atoms
3.polydentate ligand :ligand having more than two donor atoms.
(tridentate,tetradentate,pentadentate,hexadentate,etc)

Chelating ligands:
when a bidentate or a polydentate ligand is attached by two or more donor atoms to the same central metal ion or atom forming a ring structure ,the ligand is called a chelating ligand. Chelating ligand forms a ring structure around the central metal ion.

Ambident ligand:
The monodentate ligands which can coordinate with the central metal ion or atom through more than one site are called ambident ligand.e.g.CN

M CN (cyanide)
M NC(isocyanide)









2.Coordination number:
The total number of ligands attached to the central metal ion or atom is called the coordination number of the metal atom or ion.


3.Coordination sphere:
The central metal ion or atom and the ligands are collectively called the coordination sphere .
(in other words the ions present in the square bracket together are called the coordination sphere)



4. Charge of a complex:
the charge carried by a complex ion is the algebraic sum of the charges carried by the central ion and the ligands coordinated to it .

Werner's Coordination Theory - Revision Points

Postulates

1. In co-ordination compounds, central metal atoms exhibit primary valency and secondary valency.

The primary valency is ionizable. Secondary valency is not ionizable.
The primary valency corresponds to oxidation state.
The secondary valency corresponds to coordination number. (the central metal ion and ligands are not ionizable)

2. Every metal atom has a fixed number of secondary valencies (coordination number(s)).

3. The metal atom tends to satisfy boths its primary valency as well as its secondary valency. Primary valency is satisfied by negative ions (metal ion has a positive charge) whereas secondary valency (coordination number) is satisfied either by negative ions or by neutral molecules. (In certain case a negative ion may satisfy both types of valencies).

4. The coordination number or secondary valencies are always directed towards the fixed positions in space and this leads to definite geometry of the coordination compound.

Preparation of Ferrous ammonium sulphate (Mohr’s salt)

Ferrous ammonium sulphate (Mohr’s salt)

It is a double salt. A double salt is a substance obtained by the combination of two different salts which crystallize together as a single substance but ionize as two distinct salts when dissolved in water.

Mohr’s salt is prepared by dissolving an equimolar mixture of hydrated ferrous sulphate and ammonium sulphate in water containing a little of sulphuric acid and the crystallization from the solution.

On crystallization light green crystals of ferrous ammonium sulphate separate out.

Ferrous sulphate FeSO₄.7H₂O

Ammonium sulphate (NH₄)₂SO₄

Mohr’s salt FeSO₄.(NH₄)₂SO₄.6H₂O



Apparatus and materials required

Two beakers, china-dish, funnel, funnel-stand, glass rod, wash bottle, tripod stand, wire-gauze,

Ferrous sulphate crystals, ammonium sulphate crystals, dilute sulphuric acid, and ethyl alcohol.

Blog status

Presently working on Physics.

Completing revision points for all the chapters and formula revision sheets.
Next month I plan to take up mathematics.
In December I shall come back to Chemistry Chapters to revise the chapter points and make some more additions to the material.

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Tautomerism and Enols - July Dec Revision

Tautomerism

Tautomerism may be defined as the phenomenon in which a single compound exists in two readily interconvertible structures that differ markedly in the relative position of at least one atomic nucleus, generally hydrogen. The two different structures are known as tautomers of each other.

In the presence of acid or base, ketone or aldehyde with α-hydrogen is converted into hydroxyl ene (called enol), hence this type of isomerism in which keto and enol forms exist in dynamic equilibrium is also called ket-enol isomerism.


Enols

Preparation of aldehydes and ketones from alkynes

Hydration of alkynes in the presence of dilute sulphuric acid and HgSO4 as catalyst gives aldehydes and ketones.

Water adds to alkynes to form unstable enol intermediates which rearrange to form aldehydes or ketones.

Hydration of acetylene gives acetaldehyde.

Hydration of alkynes other than acetylene gives ketones.




Addition of water to alkynes (hydration of alkynes)

In the presence of acid (H2SO4) and HgSO-4, a molecule of water adds to the triple bond at 348K. The catalyst in this reaction is HgSO4 (Mercuric sulphate). The final products of this reaction are carbonyl compounds aldehydes and ketones.

Initially enol is formed which is raidly converted into an equilibrium mixture containing keto form in excess. Enol is so called because it contains 'ene' (double bond) and an alcoholic group (ol).



IIT JEE Revision - Acid Catalysed Hydration of Alkynes
In the presence of acid (H2SO4) and HgSO-4, a molecule of water adds to the triple bond at 348K.

The catalyst in this reaction is HgSO4 (Mercuric sulphate).

The final products of this reaction are carbonyl compounds aldehydes and ketones.

Initially enol is formed which is raidly converted into an equilibrium mixture containing keto form in excess.

Enol is so called because it contains 'ene' (double bond) and an alcoholic group (ol).

Example:
Addition of water to Ethyne or acytelene: Acetylene is passed into water (at about 330K) containing 60% H2SO4 and about 1% mercuric sulphate (HgSO4) as a catalyst, acetaldehyde is formed.

In the first step 'ethenol' is formed and in the second step the rearrangement of it takes place and its isomer 'acetaldehyde' is formed.

The conversion of enol form into keto form is termed tautomerism

JEE 2009 Notification

IIT Joint Entrance Examination (JEE 2009) Schedule
April 12, 2009 (Sunday)
09.00 –12.00 hrs Paper – 1
14.00 - 17.00 hrs Paper - 2

Paper – 1 and Paper – 2 will each have three separate sections on Physics, Chemistry, Mathematics. Both the papers will be objective types, designed to test comprehension, reasoning and analytical ability of candidates.

* Eligibility requirements for this examination and syllabus for Physics, Chemistry, Mathematics and Aptitude Test will be available on the websites of all IITs and will also be given in the Information Brochure of JEE – 2009.
*Candidates will have the option of submitting either on – line through internet) or paper application form- offline.
* Important dates regarding Application Form and Brochure:

Sale at designated branches of Banks and at all IITs: Nov 19 - Dec 24 2008
Postal Request of Application form: Nov 19 - Dec 16 2008
Last date of receipt of completed application forms at IITs : Dec 24 2008

Morrison and Boyd Organic Chemistry

Download Link

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Morrison and Boyd - Organic Chemistry - Slides - Notes II

Topics covered

Infrared Spectroscopy

Nuclear Magnetic Resonance

Spectrocopy Tables (IR & nmr)

Aldehydes & Ketones I

Aldehydes & Ketones II

Carboxylic Acids

Functional Derivatives of Carboxylic Acids

Carbanions I

Carbanions II

a,b-Unsaturated Carbonyls

notes on exam II

Amines, Syntheses

Amines, Reactions

Diazonium Salts

Phenols

Aryl Halides

Molecular Orbitals and Conservation of Symmetry

Polynuclear Aromatics

Heterocyclics

Carbohydrates

Fischer Proof of the Structure of (+)-glucose



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Morrison - Boyd Organic Chemistry Slides Notes

CHE-310/311 Organic Chemistry I


Available for topics





Introductory notes and review of general chemistry

Methane

Homework #6

Alkanes

Stereochemistry

Problem sets on the web for the R/S system of specification of configuration

Alkyl halides

Alcohols

Ethers

Alkenes,syntheses

Alkenes,reactions

Stereospecific and stereoselective reactions

Supplemental homework

Problem sets on the web regarding stereoselective/stereospecific reactions

Dienes

Alkynes

Exam III

Alicyclics

Aromaticity/benzene

Electrophilic Aromatic Substitution

Problem sets on the web involving electrophilic substitution reactions

Arenes



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Organic Chemistry Chapter 5 Stereochemistry: Chiral Molecules

Chapter outline

http://members.aol.com/logan20/outline5.html

PPT slides

http://nlfaculty.dcccd.edu/logan/slides/chapter5/index.htm


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Solomon Org. Chemistry Chapter 4 Alkanes and Cycloalkanes: Conformations of Molecules

Chapter Outline

http://members.aol.com/logan20/outline4.html

Nomenclature and Physical Properties of Alcohols and Ethers

http://members.aol.com/logan20/nom_alc.html

Slides

http://nlfaculty.dcccd.edu/logan/slides/chapter4/index.htm

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Solomon Organic Chemistry Ch. 3 Acids and Bases in Organic Chemistry

Chapter outline

http://members.aol.com/logan20/outline3.html

Slides

http://nlfaculty.dcccd.edu/logan/slides/chapter3/index.htm



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Solomon Organic Chemistry Chapter 2 Representative Carbon Compounds

Chapter 2 Outline

http://members.aol.com/logan20/outline2.html

Slides

http://nlfaculty.dcccd.edu/logan/slides/chapter2/index.htm

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Solomon Org Chemistry Chapter 1 Carbon Compounds and Chemical Bonds

Outline and some lecture notes

http://members.aol.com/logan20/outline1.html


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Web Links for Solomons book on Organic Chemistry

Web Links for Solomons book on Organic Chemistry


These web links, organized by chapter, provide more information about topics covered in the text and will help in your study of organic chemistry.



http://www.wiley.com/college/chem/solomons190950/weblinks.html

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Presentation - Chiral Atoms

Download the presentation from

http://docs.google.com/Presentation?id=dg3h8m78_11cpckn6gb

Chiral Molecules - July Dec Revision

Chiral molecules

A molecule is said to be chiral if it lacks symmetry and its mirror images are not superimposable. To be chiral a molecule must lack symmetry, that is, a chiral molecule can not have any type or symmetry.

Carbon atoms with four sp3 hybridized orbitals can enter into up to four different bonds about the central carbon atom.
When the central carbon bonds with differing atoms or groups of atoms the carbon is termed an asymmetric carbon atom.

Bromochlorofluoromethane is an example of such a molecule. The central carbon, with four sp3 bonds oriented (pointing) to the corners of a tetrahedron, is bonded to a bromine, chlorine, fluorine and methane atoms. There is no symmetry to this molecule.

To explain things in a more simple way, Chiral molecules are like right hand left hand. Both hands have identical fingers but in different orientations. The little finger is in clockwise direction from the middle finger in right hand, where as the little is in the counterclockwise direction in the left hand. So you can fix a right hand to another person's left wrist. Right hand and left hand are different even though all the five diffetent fingers are more or less similar in both the hands.


Enantiomers are optical isomers. A chiral molecule will have enantiomers.


A solution in which both enantiomers of a compound are present in equal amounts is called a racemic mixture, or racemate.

Fluid - July Dec revision

There is continuity between the gaseous and liquid state. The term fluid is used for either liquid or a gas to recognize this continuity. A liquid can be viewed as a very dense gas. Liquid and gas can be distinguished only when the fluid is below its critical temperature and its pressure and volume lie under the dome (in isotherm) since in that situation liquid and gas are in equilibrium and a surface separating the two phases is visible.


Chapter: States of Matter




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Relationship between Solubility and Solubility product

Relationship between solubility (S) and solubility product (K_sp)

Consider M_qA_r a sparingly soluble salt.
Where
q = Number of cations (M^r+) and
r = Number of anions (A^q-)

That is we have in dissolved state


M_qA_r ↔ qM^r+ + r A^q-


Then

K_sp = [M^r+]^q [A^q-]^r

If solubility is S, according to the definition of solubility product

We have
[M^r+]^q = q.S mol/dm³
[A^q-]^r = r.S mol/dm³

Hence K_sp = [q.S] ^q [r.S] ^r

= S^q+r. q^q.r^r


For example for the salt, calcium Phophate, Ca₃(PO₄)₂


Ca₃(PO₄)₂ ↔ 3Ca_aq²⁺ + 2PO_4(aq)^3-


K_sp = [Ca²⁺] ³ [PO₄^3-]²

= S³⁺².3³.2²
= 108S⁵

Past JEE Question

For a sparingly soluble salt A_pB_q, the relationship of its solubility product (K_sp) with its solubility (s) is

a. K_sp = s^p+q.p^p.q^q
b. K_sp = s^p+q.p^q.q^p
c. K_sp = s^pq.p^p.q^q
d. K_sp = s^pq.(pq)^p+q)

(2001)

Answer: a

Solubility Product - July Dec Revision

Solubility product of a salt at a given temperature is equal to the product of the concentrations of its ions in the saturated solution, with each concentration term raised to the power equal to the number of moles of ions produced on dissociation of one mole of the substance.

Law of Mass Action - July-Dec Revision

Law of Mass Action
For the reaction

2 NO2 = N2O4

in a sealed tube the ratio
[N2O4]
-------
[NO2]²
is a constant. This phenomenon is known as chemical equilibrium. The ratio is called equilibrium constant (K).
[N2O4] and [NO2] are molar concentrations of N2O4 and NO2.


Such a law of nature is called the law of mass action or mass action law.
Of course, when conditions, such as pressure and temperature, change, a period of time is required for the system to establish an equilibrium.
For systems that are not at equilibrium yet, the ratio calculated from the mass action law is called a reaction quotient Q. The Q values of a closed system have a tendency to reach a limiting value called equilibrium constant K over time. A system has a tendency to reach an equilibrium state.

The law of mass action may be written as:

The rate of a chemical reaction at any particular temperature is proportional to the product of the molar concentrations of reactants with each concentration term raised to the power equal to the number of molecules of the respective reactants taking part in the reaction.

In the chemical kinetics chapter we come to know that chemical reactions can be elementary reactions or complex reactions having number of elementary reactions.

Law of mass action is valid for elementary reactions.

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Chemical Equilibrium - July Dec Revision

In most of the reaction carried out in closed vessels, reaction does not go to completion under given set of conditions of temperature and pressure. Initially, in the vessel, only reactants are present, and as the reaction proceeds, the concetration of reactants will decrease and that of products will increase.

After some time a stage is reached when no further change in concetrations of reactants and products is observed. This state is called equilibrium state and some of the important questions regarding this phenomenon are:

1. why do reactions seem to stop before they reach completion?
2. What is the extent to which a reaction proceed?
3. Can we modify the conditions to improve the yield of products?

Equilibrium - The phenomenon

Equilibrium is the state at which the concentrations of reactants and products do not change with time.

It is important to remember that equilibrium is achieved in closed vessel reactions only.

The important aspect of reaction equilibrium is the reversibility. The products combine and form reactants. At equilibrium, both the forward and backward reactions are taking place. The rates of forward and backward reactions are same or equal at the equilibrium. As a result, the concentration of each species becomes constant.

The equilibrium is termed as dynamic reaction equilibrium. Dynamic means at a microscopic level, the system is in motion. But at macroscopic level, concentrations are not changing.


Chemical reactions may be classified as reversible reactions and irreversible reactions.

Example of irrereversible reaction

Decomposition of potassium chlorate into potassium chloride and oxygen. Even in a closed vessel this reaction is not reversible.

Example of reversible reaction

1. Decompositon of calcium carbonate. When solid calcium carbonate is heated in a closed vessel at 1073 K, it decomposes into solid calcium oxide and gaseous carbon dioxide. Due to gaseous CO2 there is pressure of gas in the vessel which can be measured. At a constant temperature it can be observed that pressure becomes constant after some time, which means no further CO2 is being produced even though calcium carbonate is still there in the vessel. The constant pressure indicates to us that reaction equilibrium is reached.

Characteristics of chemical equilibrium

1. Chemical equilibrium is dynamic in nature (already explained).

2. the properites of the system become constant at equilibrium and remain unchanged thereafter unless external or internal conditions are changed.

3. The equilibrium is attained only if the system is closed one.

4. As the reactions are reversible and happen under the same conditions, equilibrium can be attained from either direction.

5. A catalyst does not alter the equilibrium point. The catalyst increases the rate of reaction, and at equilibrium it increases both forward and backward reaction rates. But it does not alter equilibrium point, the concentrations of products and reactants at a given set of conditions. But the equilibrium is reached earlier in the presence of a catalyst.

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Chemical Kinetics - July December Revision

Jee Syllabus

Chemical kinetics:
Rates of chemical reactions;
Order of reactions;
Rate constant;
First order reactions;
Temperature dependence of rate constant (Arrhenius equation).
--------------------------

The topic "Chemical kinetics" consists of reaction rate and reaction mechanism.

Reaction rate is the speed with which a reaction takes place. This shows the rate or speed at which the reactants are consumed and products are formed.

Reaction mechanism is the path by which a reaction takes place.


Rate of reaction

The rate of reaction is a quantity that tells how the concentration of reactants or product changes with time.

So this can be expressed as Δ concentration/Δ time. That is change in concentration divided by time taken for the change.

Molar concentration i.e., moles per liter (M), is used in these equations.

The brackets, [ ] are always used to to indicate molar concentrations.

Rate law

The rate for a reaction is a mathematical expression that relates the rate of reaction to the concentrations of the reactants.

For the reaction aA + bB → products

The rate law is expressed as, rate of reaction is proportional to [A]^x[B]^y.
x and y are determined experimentally. These values can be whole or fractional numbers or zero.

Law of Mass Action

In 1867, Cato Guldberg, and Peter Waage, proposed this law. According to this law, for the rate determining step in a reaction, the rate of reaction is proportional to the product of the concentrations of the reactants, each raised to the power of its coefficient in the balanced equation.

For the reaction aA + bB → cC (when it is a rate determining step)

Rate of reaction is proportional to [A]^a[B]^b

The above proportionality can be written as an equation, by putting in a proportionality constant k.

Rate = k *[A]^a[B]^b

K is called the specific rate constant


Order of Reaction

From the rate law for a reaction order of reaction can be determined.

For a particular species or reactant, the order is equal to the exponent for that species in the rate law.

For example for Rate = k *[A][B]^2
for B the order of reaction is 2. For A it is 1.

The overall order of reaction is equal to the sum of all the individual orders of reactants.


Temperature

As temperature increases, the average kinetic energy increases. So there are more molecules with activation energy and hence reaction rate increases.

As a general approximation, the rate roughly doubles for each 10°C rise in temperature.

-----------

Molecularity

I recently read the lesson in NCERT Book Part I for Class XII.

There is a section on Molecularity of a Reaction

The number of reacting species which much collide simultaneously in order to bring about a chemical reaction is called molecularity of a reaction.

In the case of reaction

NH4NO2 --> N2 + 2H20

Only one molecule of the reactant decomposes. It is a unimolecular reaction. Its molecularity is one.

In case of the reaction

2HI --> H2 + I2

Two molecules of HI are involved in the reaction. It is a bimolecular reaction and its molecularity is two.

In case of the reaction

2NO + O2 --> 2NO2

2 molecules of NO and one molecule of O2 are involved. Hence it is a trimolecular reaction. The probability that more than three molecules can collide and react simultaneously is very small.

Molecularity above three is not observed. Hence reactions involving many molecules take place in steps.

Hence rate determining step will be there. Law of mass action is applicable to that step.

Lwas of Thermodynamics - July Dec Revision

Zeroth Law of Thermodynamics

If a system A is in thermal equilibrium with a system C and if B is also in thermal equilibrium with system C, then A and B are in thermal equilibrium with each other whatever the composition of the systems.


First law of thermodynamics;

Energy cannot be created or destroyed.

Energy can neither be created or nor destroyed although it can be converted from one form into another.

The energy of a system that isolated from its surroundings is constant.


Mathematical expresson for the first law

ΔU = q + w
q = heat added to the sytem
w = work done on the system

Sign conventions for heat and work

When w and q are positive, the internal energy increases. It means that energy is supplied to the system.

When w and q are negative, the internal energy decreases. It means that energy has left the system.

Chemical Energetics - Basic Terms - July Dec Revision

System

a specified part of universe which is under observation is called the system.

A system is homogeneous system if physical properties nad chemical composition are identical throughout the system. It is heterogeneous if it consists of parts each of which has different physical and chemical properties.

surroundings

The remaining portion of the universe which is not part of the system is termed the surroundings.

Open system: A system which can exchange matter as well as energy with the surroundings is called an open system.

Closed system: A system which can exchange energy but not matter with the surroundings is called a closed system.

Isolated system: A system which can neither exchange matter nor energy with the surroundings is called an isolated system.

Macroscopic properties

Pressure, Volume etc. are related to the behavior of the bulk of the material. These properties are called macroscopic properties.

the macroscopic properties are divided into types.

1. Intensive properties 2. Extensive properties

1. Intensive properties: These properties have no relation to the amount of substance present in a system. Examples: temperature, pressure, viscosity, surface tension, refractive index etc.

2. Extensive properties: The value of these properties depends upon the amount of substance present in the system.

Examples: Mass, volume, surface area, energy, enthalpy, entropy, free energy, heat capacity

State Variables and State Functions

The state of a system is described by macroscopic properties when they are stable and have definite values. If any of the macroscopic properties of the system changes, the state of the system changes.

We describe a system by its state variables. A system having ideal gas can be described by three state variables. These three variables are : temperature (T), pressure (p) and volume (V). Once these three variables are specified all the other variables will be definite and can be easily calculated.

State function is a property of the system whose value depends only upon the state of the system and is independent of the path or manner by which the state is reached.

A system is said to be in thermodynamic equilibrium when the macroscopic properties do not change with time.




Processes

Isothermal: Temperature of the system is constant.

Adiabatic: No heat flows into or out of the system.

Isochoric: volume of the system remains the same.

Isobaric: Pressure of the sytem remains the same.

Reversible: The system changes in infinitesimal steps and they can be reversed.

Irrevesible: Real life systems do not satisfy the reverbility criterion and hence irreversible.

Cyclic: a process in which the system undergoes a series of changes and ultimately returns to its original state is called a cyclic process.

Modes of transfer of energy between system and surroundings

1. Heat (Q): Energy is exchanged between the system and the surroundings as heat if they are at different temperatures.

2. Another modes of transfer of energy is work. Work is said to be performed if th point of application of a force is displaced in the direction of the force.

Pressure volume work

Pressure volume work is mechanical work. It is the work done when the gas expands or contracts against external pressure.

It is equal to force multiplied by distance moved or pressured mulitiplied by change in volume.

Units of Heat and Work

S.I. unit of heat is joule or kilojoule
S.I. unit of work is also joule or kilojoule

Joule and calories are related by the relation

1 cal = 4.184 J
1 kcal = 4.184 kJ

Kinetic theory of gases - July-Dec 2008 revision

Kinetc theory of gases is also called kinetic molecular theory of gases.

The model takes into account molecular concept and the kinetic concept of gas molecules.

The theory was put forward by Bernoulli and was further developed and extended by Clausius, Maxwell, Boltzmann and others.

Postulates of the theory

1. All gases are made up of large number of minute particles called molecules.

2. The molecules are separated from one another by large distances.

3. The molecules are in a state of ceaseless and random motion in all directions. They keep colliding with other molecules and walls of the container and change their directions.

4. Molecular collissions are perfectly elastic (See physics for concept of elastic collisions)

5. There are no forces of interaction (attrative or repulsive) between molecules.

6. The pressure exerted by the gas is due to the collisions of the its molecules on the walls of the container per unit area.

7. Teh average kinetc engery of the gas molecules is directly proportional to the absolute temperature.

Kinetic gas equation

From the postulates of kinetic molecular theory, an equation was derived for the pressure of the gas. This equation is known as kinetic gas equation and is

pV = 1/3 mNu²

where

m = mass of a molecule
N = the number of molecules in the volume V
u = root mean square velocity of the molecules. u² is the mean square velocity of molecules. The velociytof each molecule is first squared and then its average is taken.

Averge Kinetic Energy of Molecules of a gas

The average translational kinetic energy of a molecule is

1/2 mu²

where

m = mass of a molecule

u = root mean square velocity of the molecules. u² is the mean square velocity of molecules. The velociytof each molecule is first squared and then its average is taken.

The total kinetic energy of the whole gas is

Ek = 1/2 mNu²

From the formulas for pV and Ek we can get

pV = 2/3 Ek

If we take one mole of gas and define Ek as total kinetic energy of one mole of gas

pV = RT = 2/3 Ek

=> Ek = 3/2RT for one mole of gas

For n moles of gas
Ek = 3/2 nRT.

If we want averge kinetic energy of one molecule, we divide Ek of one mole by Avogadros' number N_A(6.022*10²³).

averge kinetic energy of one molecule = (3/2) RT/N_A = 3/2k_bT

Where k_b = R/N_A is called Boltzmann constant.

Thus Ek α T

As Kinetic energy is proportional to u²

u² α T

u α √T

Molecular velocity of any gas is directly proportional to the square root of the absolute temperature.

This molecular motion is also referred to as thermal motion of the molecules. It will be zero when T = 0.



Past IIT JEE Questions

1. Helium atom is two times heavier than a hydrogen molecule. At 298 K, the average kinetic energy of a helium atom is

a. same as that of a hydrogen molecule
b. two times that of a hydrogen molecule
c. four times that of a hydrogen molecule
d. half that of a hydrogen molecule
(JEE 1982)

Answer: (a)




2. State whether the statement is True or False.

Kinetic energy of molecules is zero at 0°C. (JEE 1985)

Ans: False

The equation relating energy of molecules to temperature is in absolute temperature and not centigrade temperature.


3. the average velocity of an ideal gas molecule at 27°C is 0.3 m/s. the average speed at 927°C will be:

a. 0.6 m/s
b. 0.3 m/s
c. 0.9 m/s
d. 3.0 m/s
(JEE 1986)

Answer: (a)


4. Eight grams of oxygen and hydrogen at 27°C will have the total kinetic energy in the ratio of __________________.
(JEE 1989)

Answer: 1:16

Reason: For a mixture of gases, in thermal equilibrium, average kinetic energy of all molecules is same.

(½)*m1* v1² = (1/2)*(m2*v2²

Oxygen’s molecular weight is 32 and hence 8 grams will have 8/32 = ¼ moles.
Hydrogen’s molecular weight is 2 and hence 8 grams will have 8/2 = 4 mols

Total kinetic energy of oxygen moleculues = (¼ )* (½)*m1* v1²
Total kinetic energy of hydrogen molecules = 4*(1/2)*(m2*v2²

The ratio will be (1/4)/4 = 1/16 as remaining terms or equal in both cases.

Criterion of Spontaneity and Free Energy

July-December Revision

The flow of heat takes from a body at high temperature to a body at low temperature through conduction, convection or radiation. Similarly a liquid at higher level flows to a lower level. In both these cases the action occurs without any additional support. But if a liquid at lower level has to go higher level additional supporting activity is required.

Similarly in chemical reactions some reactions take place if the reactants are in contact. Some reactions will not take place through contact but require additional inputs like heat, catalysts etc. Reactions that take place due to contact alone are called spontaneous reactions. The rate of reaction is not the issue here. Even if the rate of reaction is very slow, if the reaction is taking place, it is a spontaneous reaction.

What determines the spontaneity of a chemical reaction?

Is decrease in enthalpy in the reaction a criterion for spontaneity?

In exothermic reactions, enthalpy of products is less than that of reactants. Thus some persons postulated that a spontaneous chemical reaction may be due to decrease in energy of the products. It sounds reasonable. But some scientists found that some endothermic reactions are also spontaneous. Therefore it is concluded that enthalpy may be a contributory factor for spontaneity, but it is not the complete explanation.

Is entropy a criterion for spontaneity?

Entropy is a thermodynamic function. It can be interpreted as measuring disorder in the system. A gas is more disordered than a liquid and a liquid is more disordered than a solid. In a chemical reaction, if the disorder in products is more than that of reactants, entropy increases. It is found in examples like diffusion of gases etc. that in spontaneous activities disorder increases.

As heat is added to the system, solids become liquids and liquids become gases. Hence heat increases entropy. Entropy is defined as

ΔS = q_rev/T for a reversible reaction.

The criterion of spontaneity is defined by the total entropy change of system and surrounding. The total entropy change (ΔS_total) for the system and surroundings of a spontaneous process is given by


ΔS_total = ΔS_system + ΔS_surrounding > 0

Gibbs energy of Free energy

Gibbs energy or Gibbs function is a thermodynamic functions defined by

G = H-TS

For a constant temperature reaction

ΔG_sys = ΔH_sys -T ΔS_sys

Criterion for spontaneity in terms of Gibbs energy or function is that

If ΔG is negative or< 0, the reaction will be spontaneous.

This condition comes from the condition that was given above only. That is

ΔS_total = ΔS_system + ΔS_surrounding > 0

ΔS_surr = ΔH_surr/T = -ΔH_sys/T (because what system loses surrounding gains and vice versa)

Hence
ΔS_total = ΔS_system - ΔH_sys/T

=> TΔS_total = TΔS_system - ΔH_sys
As spontaneity criterion is ΔS_total > 0

RHS must be greater than 0.
=> TΔS_system - ΔH_sys > 0
=> -( ΔH_sys - TΔS_system) > 0
=> ( ΔH_sys - TΔS_system) < 0

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Read about Naga Naresh Karutura who has just passed out of IIT Madras in Computer Science and has joined Google in Bangalore.

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Ch.1 Basic concepts of Chemistry - July-Dec 08 Revision

JEE Syllabus

General topics:

The concept of atoms and molecules;
Dalton's atomic theory;
Mole concept;
Chemical formulae;
Balanced chemical equations;
Calculations (based on mole concept) involving common oxidation-reduction, neutralisation, and displacement reactions;
Concentration in terms of mole fraction, molarity, molality and normality.
---------
Accuracy

Accuracy is a measure of the difference between the true value (the value to be measured) and the value measured by an instrument.

Precision is depends totally on the instrument and it is the difference between measurements of the same dimension made number of times. It is expressed as the difference between one measurement and the arithmetic mean of the number of measurements.

Significant figures: Significant figures in a number are include all the certain digits plus one doubtful digit.

If a number has 4 significant figures or digits, it means 3 of them are certain and fourth one is doubtful.

Rules for determining the number of significant figures

1. All non-zero digits are significant
Decimal place does not determine the number of significant figures.

2. A zero becomes significant in case it comes between two non-zero numbers.
3. The zeros at the beginning of a number are not significant.
For example 0.0004 has only one significant figure.
4. All zeros placed to right of a number are significant. They represent the precision of the measuring scale.
For example 267.000 has six significant figures.
(The precision does not come by writing the number. It comes because the instrument has the ability to read a number certainly up to that level of measurement.)

Rules of calculations involving significant figures

Rule 1. The final result of addition or subtraction should be reported up to the same number of decimal places as are present in the term having the least number of decimal places.
Example- addition of three numbers
6.414
2.3
0.501
------
9.215 is the answer but the answer should be reported up to one decimal place only as 2.3 is the term having least number of decimal places.

Hence correct answer is 9.2

Rule 2. In multiplication or division, the final result should be reported up to the same number of significant figures as are present in the term with the least number of significant figures.
Example: 4.2345*1.25 = 5.293125
The final result should be reported up to three significant figures only as 1.25 has three significant figures. Hence the correct answer to be reported is 5.29.

Rounding off figures of retention of significant figures.

i) If the digit coming after the desired number of significant figures happens to be more than 5, the preceding digit or figure is increased by 1.
ii) If that digit is less than 5, it is neglected and hence the preceding significant figure remains unchanged.
iii) If that digit happens to be 5, the preceding digit is increased by one in case it is odd number. If preceding digit is an even number, it remains the same.

If the problem has number of steps, the rounding off is to be done at the final answer level only.

Chemical classification of matter

1. Element
Further classification: Metals, non-metals, metalloids
2. Compound
Further classification: Inorganic and organic
3. Mixture
Further classification: Homogeneous mixtures - they are called solutions.
Heterogeneous mixtures: They have visible boundaries of separation between the different constituents and they can be easily seen with naked eye.


Laws of chemical combination


a. Law of conservation of mass
During any physical o chemical change, the total mass of the products is equal to the total mass of reactants.

b. Law of constant proportions

A pure chemical compound always contains same elements combined together in the same definite proportion by weight.
c. Law of multiple proportions

When two elements combine to form two or more than two compounds, the weights of one of the elements which combine with a fixed weight of the other, bear a simple whole number ratio.

d. Law of reciprocal proportions
When two different elements combine separately with the same weight of a third element, the ratio in which they do so will be the same or some simple multiple of the ratio in which they combine with each other.

e. Gay Lussac’s law of combing volumes
Under similar conditions of temperature and pressure, whenever gases react together, the volumes of the reacting gases as well as products (if gases) bear a simple whole number ratio.
---------------
Dalton’s atomic theory

To provide theoretical justification to the laws of chemical combination which are experimentally verified, John Dalton postulated a simple theory of matter. The basic postulates of Dalton’s atomic theory are:

a. Matter is made up of extremely small indivisible and indestructible ultimate particles called atoms.
b. Atoms the same element are identical in all respects ie., in shape, size, mass and chemical properties.
c. Atoms of different elements are different in all respects and have different masses and chemical properties.
d. Atom is the smallest unit that takes part in chemical combinations.
d. Atoms of two or more elements combine in a simpler whole number ratio to form compound atoms (molecules).
e. Atoms can neither be created nor destroyed during any physical or chemical change.
f. Chemical reactions involve only combinations, separation or rearrangement of atoms.

Modern atomic theory
As a result of new discoveries made after Dalton developed his postulates, some modifications were done to atomic theory. They are:

1. Atom is no longer considered to be indivisible: It is found that atom is made up of subatomic particles such as electrons, protons and neutrons. We now state how many electrons are there, protons are there in an atom.

2. Atoms of same element may not be similar in all respects. Atoms of same elements have different atomic masses. These different atoms are called isotopes.

3. Atoms of different elements may have similar one or more properties. Atomic mass of calcium and argon (40 a.m.u.) are same. So the property of atomic mass is same for atoms of different elements. Isobars or elements or atoms having the same atomic mass.

4. Atom is the smallest unit which takes part in chemical reactions. Though electrons and protons are there, it is atom which takes part in chemical reactions and electrons exchange takes place between atoms.

5. The ratio in which the different atoms combine may be fixed and integral but may not always be simple. For example in sugar molecule the ratio of C,H and O atoms is 12:22:11, which is not simple.

6. Atom of one elements may be changed into atoms of other element. Transmutation is the process by which atoms one element can be changed inot elements of other elements by subjecting it to alpha rays.

7. The mass of atom can changed into energy. Mass and energy are inconvertible. The equation give for such conversion is E mc². Hence we cannot say that mass is not destructible. But in chemical reactions, atom remains unchanged and its mass is not destroyed to liberate energy.


----------
Mole concept
A mole is measuring unit like for example dozen.
A mole is a collection of 6.022*1023 particles






Stochiometric coefficients or numbers: The numbers which appear before the chemical symbols in a chemical equation.

Chemical equation gives information about moles of various reactants and products. Hence molar masses involved in the reaction and molar masses of products.

Mass percentage of substance in a system

Mole fraction of a substance in a system

--------------
Concentration in terms of mole fraction, molarity, molality and normality.

Mole fraction of a substance in a system: It is the ratio of number of moles one component to the total number of moles (solute and solvent) present in the solution. It is denoted by x.

So mole fraction of solute = Moles of solute/(Moles of solute + Moles of solvent)

Mole fraction of solvent = Moles of solvent/(Moles of solute + Moles of solvent)

MOLARITY = Amount of a substance (in mol)/Volume of solution expressed in dm^3
It is applicable to solutions only.

Also equal to No. of moles of solute/Vol. of solution in litres or dm^3

The unit of molarity is mol dm^-3. It is commonly abbreviated by the symbol M and is spelled as molar.

MOLALITY = Amount of a a substance (in mol)/Mass of solvent expressed in kg
It is also applicable to solutions only

CONCEPT OF EQUIVALENT
__________________________

"One equivalent of a substance in a reaction is defined as the amount of substance which reacts or liberates 1 mol of electrons or 1 mol of H^+ or 1 mol of OH^- ions.

The equivalent weight of a reagent may vary according to the reaction, but
if considering just acid and base moles and equivalents, then:-

H2SO4 + 2 NaOH -> 2H2O + Na2SO4

The equivalent weight of an acid is that which contains 1.0078 grams of replaceable hydrogen which, in the case of sulfuric acid, would be half the mole weight, because 1 mol of H2SO4 is liberating 2 moles of H^+ ions

In the case of hydrochloric acid, equivalent weight would be the mole weight as 1 mol of HCl liberates 1 mol of H^+ ions.

The equivalent weight of a base is that which contains one replaceable hydroxyl group ( i.e., 17.008g of ionisable hydroxyl ). Thus the equivalent weight of sodium hydroxide ( NaOH ) and potassium hydroxide ( KOH ) would be the mole weight, but for calcium hydroxide ( Ca(OH)2 ) it would be half the mole weight.

Normality

A Normal solution contains one gram equivalent weight ( aka equivalent )
of the reagent in one litre of solution, and is represented by " N ".

Normality = (equivalents of X (solute))/volume of solution in Liters or dm³

Normality = molarity x n (where n = the number of protons exchanged in a reaction).

July - December 2008 Revision

I plan to go through each chapter in Chemistry, Physics and Mathematics in revision mode during July-December 2008 apart from reading or studying chapter which I have not read so far.

My thinking is that from 1st January 2009 onwards, the aspirants should focus on memorizing things and a revision during July-Dec at leisurely pace, one chapter per day would help in that. From 1 January 2009, the memorization process should take up three chapters per day.

Carboxylic Acid - July-December Revision

JEE syllabus

Carboxylic acids:
Preparation, properties
Characteristic reactions
formation of esters,
acid chlorides and amides,
ester hydrolysis;
---------
I. Carboxylic acids are the compound containing carboxyl group in their molecules.

-C with a double bond with oxygen and single bond with OH

O
║
C
|
OH

II. These acids can be aliphatic or aromatic.

aliphatic acids:

Formic acid HCOOH
Acetic acid CH-3COOH
Isobutyric acid (Branched)

Aromatic acids

Bezoic acid : H in benzene substituted by COOH. It is the simplest aromatic carboxylic acid.

m-Nitrobenzoic acid: One more H substituted by NO-2

o-Toluic acid (o refers to ortho) Benzoic acid with one more H substituted by CH-3

III. Methods of Preparation of Monocarboxylic Acids:

1. From oxidation of primary alcohols

2. By oxidation of aldehydes and ketones.

3. From hydrolysis of nitriles and cyanides
the nitriles are hydrolysed in dilute acqueous acidic or alkaline medium.

4. From Grignard reagents
The reaction is carried out by bubbling CO2 through the etheral solution of suitable Grignard reagent.

5. By hydrolysis of esters
Hydrolysis of esters with mineral acids or alkalines gives carboxylic acids

6. Carboxylation of alkenes
Heating alkenes with CO and steam under pressure with phospoiric acid at 673 K. This reaction is called Koch reaction.

7. From trihalogen derivatives of hydrocarbons
Hydroysis of 1,1,1,-trihalogen derivatives of alkanes with acqueous KOH.

8. Preparation of aromatic acids from alkyl benzenes
the alkyl side chain of benzene ring can be easily oxidized to carboxylic group with alkalines KMnO4, chromic anhydride or conc. HNO3.

More Revision of Carboxylic Acid

One of the carboxylic acid of relevance in soap making

common name: Strearic acid

CH₃CH2)₁₆COOH

IUPAC Name Octadecanoic acid

Sodium stearate is soap.

Triglyceride is a triester of glycerol with fatty acids.

Fatty acids are carboxylic acids.

Formation of esters

When carboxylic acids are heated with alcohols in the presence of concentrated H2SO4, esters are formed. The reaction is reversible and is called esterification.


From the materials on esters

Hydrolysis of esters

Esters are slowly hydrolysed by water at reflux temperatures. The reaction is accelerated by dilute mineral acids (HCl, H2SO4) or alkalies.

Hydrolysis of esters by alkalies is also known as saponification and leads to formation of soaps.

Glycerol - Revision

I came across glycerol as I am browsing through a CET guide on chemistry in the section on oils and fats. I went back to organic chemistry text to locate glycerol. There is a need to think of various concepts repeatedly to recollect them when needed.


Glycerol is a triol.

The alcohols with three –OH groups are named as triols.

It is also termed as trihydroxy alcohol.

Glycerol is formed when 3 Hs of Propane (C3H8) are replaced by 3 OH groups.

Glycerol is C3H5(OH)3 = OHCH2-OHCH-OHCH2

CH2-OH
|
CH-OH
|
CH2-OH

Triglycerides (glyceride or triacyl glycerol or oils or fats)

When glycerol (glycerine) is heated with fatty acid, triglycerides are produced. Tyiglycerides have wide application in preparation of soap, paints, varnishes, ink, ointments and cream.

Fatty acid is represented is a monocarboxylic acid and is represented as HOOCR

CH2-OH
|
CH-OH + 3HOOCR
|
CH2-OH

will give


CH2-OOCR
|
CH-OOCR
|
CH2-OOCR

and 3H2O

Formation of soap

Soap is a sodium or potassium salt of fatty acid. Alkaline hydrolysis of triglycerides to form soap and glycerol is known as saponification.

Fatty acid + NaOH (Acqueous) → soap + glycerol

On completion of saponification precipitate of soap is completed by common ion effect. For this saturated solution of NaCl (brine) is used.

Sodium soaps are hard and hence used as washing soap. (ex. Sodium stearate)
Potassium soaps are soft and hence used as bathing soap.(Ex. Potassium oleate (remember Oil of Olay), Potassium stearate)

Nomenclature - Carboxylic Acids

Nomenclature


The common names of carboxylic acids are based on their source of origin. Formic acid was first obtained from red ants (Latin formica means red ants) and it was named from that. Acetic acid was obtained from vinegar (Latin aceum means vinegar) and so got that name.

In the common system the position of substituents is indicated by the Greek letters α, β, γ, ō.

α, β, γ, ō Carbon atoms

The carbon atom next to the carboxyl carbon is assigned the letter α. The carbon next to α-carbon is the β-carbon. The carbon next to β-carbon is the γ-carbon. The carbon next to γ-carbon is the ō Carbon.

ō-γ-β-α carbons
C-C-C-C-COOH


IUPAC System

According to IUPAC system, the name of the monocarboxylic acid is derived by changing the final 'e' from the name of the corresponding hydrocarbon with 'oic' and adding the word acid.

Formic acid - Methanoic acid
Acetic acid - Ethanoic acid
n-Butyric acid - Butanoic acid
Isobutyric acid - 2-Mehtylpropanoic acid

Dicarboxylic acids

Oxalic acid - Ethanedioic acid
Malonic acid - Propanedioic acid

The position of substituents is indicated by the following rules.

1. The longest chain of carbon atoms containing the carboxylic group(-COOH) is selected.
2. The numbering of carbons starts from the carboxylic acid group and the carbon of carboxyl group is given number 1.
3. The position of the substituents is indicated by the number of carbon atom to which they are attached.



Aromatic carboxylic acids

The simplest aromatic carboxylic acid is benzoic acid.

The IUPAC names of substituted aromatic carboxylic acids are derived by prefixing the name of the substituent to the name of the parent acid i.e., benzoic acid and the position is indicated by an Arabic numeral with the carbon atom carrying the –COOH group being numbered as 1.

Ionisation

When an elctrolyte is dissolved in water, it splits up into ions.

For example, sodium chloride is the solid state exists as a collection of positively charged sodium ions and negatively charged chloride ions. These are held together by strong electrostatic forces of attraction in the solid state. Due to these strong attractive forces, the ions do not move freely and therefore do not conduct electricity in the solid state.

Ionisation process: When such a compound (NaCl) is dissolved in water, a high dielectric constant of water cuts down the forces of attraction between the ions. As a result, the ions get separated and dissolve in water.

The forces of attraction between oppositely charged ions are inversely proportional to the dielectric constant of the medium. The grreaer the dielectric constant, teh greater is the dissolving power of the solvent. The dielectric constant of water is 80 and therefore, these forces are reduced by a factor of 80 in aqueous solutions and ions become free to move.



(Topic: Ionic equilibrium)

Lewis Concept of Acids and Bases (1923)

An acid is a substance (molecule or ion) which can accept a pair of electrons.

A base is a substance (molecule or ion) which can donate a pair of electrons.


Species that can be Lewis bases

(i) Neutral species (substances) having at least one lone pair of electrons

Ammonia, amines, alcohols

(ii)Negatively charged species (anions)

chloride ion, cyanide ion, hydroxide ion etc.

Species that can be Lewis acids

(i)Molecules in which the central atom has incomplete octet

BF3, AlCl3, FeCl3

(ii) Simple cations.
Some cations like Na+, K+, Ca²+ have very little tendency ot accept electrons.
But cations like H+, Ag+ etc. hve a greater electron accepting tendency and therefore act as Lewis acids.

(iii) Molecules in which the central atom has empty d-orbitals.
Molecules such as SiF4, SnCl4, and PF5 have their central atoms with empy d- orbitals. They can expand their outer octet by accepting electrons from other substances.

(iv) Molecules in which atoms dissimilar electronegativities are joined by multiple bonds.

In these molecules, electrons one atoms are pulled towards it by the other atom. Due to this, under the influence of the attacking Lewis base, the pair of electrons in the π-bond or one of the π-bonds(if more than one multiple bond is there like CO2) will be shifted toward the oxygen atom and the pair donated by the Lewis base is accepted.


All Bronsted bases are also Lewis bases.
But all Bronsted acids are not Lewis acids. For instance, HCL, H2SO4 can give a proton but cannot accept a pair of electrons.

Bronsted - Lowry Concept of Acids and Bases (1923)

According to Bronsted - Lowry Concept:

An acid is a substance which can donate proton (H+):

A base is a substance which can accept a proton (H+).

All Arrhenius acids are also Bronsted acids.
But all Arrehenius bases are not Bronsted bases.

For example, NaOH is a base according to Arrhenius theory because it gives OH- ions in aqueous solution. But NaOH does not accept a proton. Thus it may not be classified as a base according to Bronsted theory.



Conjugate acids, bases

The pairs of acids and bases whihc are formed from each other by the gain of loss of a proton are called conjugate acid-base pairs.


(Topic: Ionic equilibrium, Redox reactions)

Arrhenius Concept of Acids and Bases

An acid is a substance which dissociates in acqueous solution to give hydrogen ions.

A base is a substance which dissociates in acqueous solution to give hydroxyl ions


Acids give H+ ions in water, bases give OH- ions in water

Avogadro's Law

Under similar conditions of temperature and pressure, equal volumes of all gases contain equal number of molecules.

(Basic concepts of chemistry)

Laws of Chemical Combination

1. Law of conservation of mass

During any physical or chemical change, the total mass of the products is equal to the total mass of reactants.

2. Law of constant proportions

A pure chemical compound always contains same elements combined together in the same definite proportion by weight.

3. Law of multiple proportions

When two elements combine to form two or more than two compounds, the weights of one of the elements which combine with a fixed weight of the other, bear a simple whole number ratio.

4. Law of reciprocal proportions

When two different elements combine separately with the same weight of a third element, the ratio in which they do so will be the same or some simple multiple of the ratio in which they combine with each other.

5. Gay Lussac’s law of combing volumes

Under similar conditions of temperature and pressure, whenever gases react together, the volumes of the reacting gases as well as products (if gases) bear a simple whole number ratio.

If you can dream it, you can do it

The starting point of all achievement is desire.

Keep this constantly in mind. Weak desires bring weak results, just as a small amount of fire makes a small amount of heat.

NAPOLEAN HILL, PIONEER OF PERSONAL-SUCCESS LITERATURE

Read the article by Ankur Gupta in Hindustan Times, 6th July 2008 page No. 9

I shall give the summary and important points at a later date.

Why is SO3 is Lewis Acid?

I remember somebody asking this question in comments. I could not locate the answer at that time in the books that I referred to at that time.

Today I came across the issue in Inorganic Chemistry by Dr.O.P.Tandon, 2007 edition, page 120.


It says

Molecules haivng a multiple bond between atoms of dissimilar electronegativity act as Lewis acids. Typical examples of molecules belonging to this class of Lewis acids are CO2, SO2 and SO3. Under the influence of attacking Lewis base, one π-electron pair will be shifted towardsmore negative atom.

In page 128 question (viii) is more direct.

So# has acidic behaviour. Explain

Hint:Sulphur atom is attached with three very highly electronegative oxygen atoms. As a result, electrons are drawn towards oxygen atoms and S-atom remains wiht electron density and thus has the tendency to accept electrons. So it acts as a Lewis acid.

Organic Chemistry the Easy Way

Organic Chemistry the Easy Way

By
Bruce A. Hathaway, Bruce A. Hathaway Ph.D.
2005

YOu can have a limited preview of it in google books

http://books.google.co.in/books?id=fjy2oJuJ_0kC&printsec=frontcover&dq=Organic+Chemistry+the+Easy+Way&sig=W7wzRWnDB0jNu-b6eq3a-secEHo

Blog status

Revision points of spectrum of hydrogen atom are updated.

http://iit-jee-chemistry.blogspot.com/2008/02/spectrum-of-hydrogen-atom.html

Acquired NCERT Books

Today I acquired the NCERT books of Chemistry Class XI and XII to help me in JEE studies.

Silicon

Molecular Formula Si

Silicon Si;

Atomic weight 28.0855
Atomic number 14;
valence 4
Melting point 1414 deg C;
Boiling point 3265 deg C;
sp. gr. 2.33 (25 deg C);

Berzelius, generally credited with the discovery, in 1824 succeeded in preparing amorphous silicon by removing the fluosilicates by repeated washings. Deville in 1854 first prepared crystalline silicon, the second allotropic form of the element.

Silicon is present in the sun and stars and is a principal component of a class of meteorites known as "aerolites". It is also a component of tektites, a natural glass of uncertain origin.

Natural silicon contains three isotopes.

Fourteen other radioactive isotopes are recognized.

Silicon makes up 25.7% of the earth's crust, by weight, and is the second most abundant element, being exceeded only by oxygen.

Silicon is not found free in nature, but occurs chiefly as the oxide and as silicates. Sand, quartz, rock crystal, amethyst, agate, flint, jasper, and opal are some of the forms in which the oxide appears. Granite, hornblende, asbestos, feldspar, claymica, etc. are but a few of the numerous silicate minerals.

Silicon is prepared commercially by heating silica and carbon in an electric furnace, using carbon electrodes. Several other methods can be used for preparing the element.

Amorphous silicon can be prepared as a brown powder, which can be easily melted or vaporized.

Crystalline silicon has a metallic luster and grayish color.

The Czochralski process is commonly used to produce single crystals of silicon used for solid-state or semiconductor devices. Hyperpure silicon can be prepared by the thermal decomposition of ultra-pure trichlorosilane in a hydrogen atmosphere, and by a vacuum float zone process.

This product can be doped with boron, gallium, phosphorus, or arsenic to produce silicon for use in transistors, solar cells, rectifiers, and other solid-state devices which are used extensively in the electronics and space-age industries.

Hydrogenated amorphous silicon has shown promise in producing economical cells for converting solar energy into electricity.

Silicon is a relatively inert element, but it is attacked by halogens and dilute alkali. Most acids except hydrofluoric, do not affect it.

Silicones are important products of silicon. They may be prepared by hydrolyzing a silicon organic chloride, such as dimethyl silicon chloride. Hydrolysis and condensation of various substituted chlorosilanes can be used to produce a very great number of polymeric products or silicones, ranging from liquids to hard, glasslike solids with many useful properties.

Elemental silicon transmits more than 95% bf all wavelengths of infrared, from 1.3 to 6.7 um.

Silicon is one of man's most useful elements. In the form of sand and clay it is used to make concrete and brick; it is a useful refractory material for high-tempemture work, and in the form of silicates it is used in making enamels, pottery, etc.

Silica, as sand, is a principal ingredient of glass, one of the most inexpensive of materials with excellent mechanical, optical, thermal, and electrical properties. Glass can be made in a very great variety of shapes, and is used as containers, window glass, insulators, and thousands of other uses.

Silicon tetrachloride can be used to iridize glass. Silicon is important in plant and animal life. Diatoms in both fresh and salt water extract silica from the water to build up their cell walls.

Silica is present in ashes of plants and in the human skeleton. Silicon is an important ingredient in steel;

silicon carbide is one of the most important abrasives and has been used in lasers to produce coherent light of 4560 A.

Miners, stonecutters, and other engaged in work where siliceous dust is breathed in large quantities often develop a serious lung disease known as silicosis.


http://www.speclab.com/elements/silicon.htm

Intensive Study Diary

The time has come for intensive study. It means solving lots of problems.

Week ending 25th May Basic concepts in Chemistry - Mole concept, Stochiometry

IIT JEE Blog Status

These days I am posting new things in Chemistry blog. I first completed chemistry adn then shifted my attention to Physics. I read both the books of physics of HC Verma, prepared consolidated JEE past question lists in some of the topics like thermal physics and modern physics.

I am presently reading mathematics chapters. I found R D Sharma comprehensive for theory of JEE syllabus. I have TMH maths also. Presently reading Sharma. I am posting section headings in various chapters of Sharma to facilitate recall of the material after study of a chapter. These posts are in Mathematics Practice sets blog.

http://iit-jee-maths-ps.blogspot.com/

I posted some concepts and formulas in regular maths blog

iit-jee-maths.blogspot.com/

IIT JEE Chemistry - Useful Books - Download

I found these two useful materials from scribd.com today

Illustrated periodic table
http://www.scribd.com/doc/2288506/PeriodicTableIllustrated




A-Guide-to-Solvents-and-Reagents
http://www.scribd.com/doc/2319210/A-Guide-to-Solvents-and-Reagents

IIT JEE 2010 Chemistry Study Plan

Chapters to be completed from IIT JEE Syllabus during XI class (2008-09)


Chemistry Class XI Chapters (Maharashtra syllabus)

1. Some basic concepts of chemistry
2. States of matter
3. Atomic structure
4. Periodic table
5. Redox reactions
6. Chemical equilibrium
7. Adsorption
8. Nature of chemical bond
9. S-block elements
10. P-block elements
11. Principles and methods of purification of substances
12. Chemistry of carbon compounds
13. Alkanes
14. Alkenes
15. Alkynes
16. Aromatic compounds


Chapters to be completed from IIT JEE Syllabus during XI class (2008-09)

Gaseous, liquid and solid states
Atomic structure
Bonding and molecular structure
Chemical equilibrium
Surface chemistry
Non metals
Compounds of metals
Compounds of non metals
Organic chemistry – Nomenclature and isomerism
Alkanes
Alkenes
Alkynes
Benzene

IIT JEE 2009 Study Strategy

If you are with a coaching institute, the institute will set the strategy. Cooperate with the institute and faculty totally.

If you are using postal coaching or studying on your own then you need to put in place your own strategy.

Plan to complete the complete syllabus by December 2008.

According to the scheme of syllabus that I am following

Physics has 47 lessons (HC Verma)
Chemistry has 34 lessons
Mathematichs has 27 lessons

If you have completed some lessons already you are at an advantageous position.

Otherwise you need a plan to complete 108 lessons in 8 months. (May to December 2008) That gives a figure of 13 to 14 lessons a month. A lesson in two days.Combine some lessons that you studied in the first year with some lessons in the second year in your plan.

At the end of two days you should be able to completely answer all the worked out problems related to the chapter.When you are going through the problems put a mark on the problems that you feel are difficult. You can go through them some more times to make them easy for you.

Every Sunday, you need to write a test on the three chapter that you studied in that week plus all the earlier chapters. Ask your parents to set up the test from the questions in the study guides that you are studying.If you bought some test paper series you can use that. I want to develop a set of model papers but I may not be able to do it this year.

Prepare a monthly plan of the chapters that you intend studying in that month and try to stick to it every week.

JEE 2010 Aspirants - Preparation Strategy

I started studying IIT JEE materials in May 2007. So far I studied the full material of Physics and Chemistry. In Mathematics I just studied the principles and I have to do some problems.

Of course I don't have to write the examination. I am doing the study to help my child (2009) and then children of my brothers and sisters.

According to my thinking,the decision to appear for JEE must be taken and preparation started right from the day, the X class examinations are over. The attitude must be to remember the materials learned in the X class. A revision of the X material after the examination will lay the firm foundation for JEE preparation.

May 2008 to December 2008 must be used to complete the entire syllabus of 11th class. Read the lessons in your XI class text and simultaneously read the material in JEE level texts that you buy. Approximately 3 lessons of Physics, Chemistry and Mathematics (one each) must be completed every 10 days. That way you can read 9 lessons a month. In eight months you can complete 72 lessons. As the books are written you may not have 24 chapters in every subject. But the chapters are very big and you can practically treat them as two chapters.

That will give you time to revise you XI material during January-April 2008. Will give you good amount of time to concentrate on Board examianations and other subjects in the course.

I have seen the coaching institutes giving an IIT examination every alternate Sunday. They are giving it for six hours right in the first year itself. I recommend a three hour examination every two weeks with cumulative syllabus in the first year. Every alternate week, a one and half examination could be there in one lesson each of Chemistry, Mathematics and Physics. Prepare and write the examination conducted by your coaching institute enthusiastically. Your positive attitude right from the day one will help you immensely. Cooperate with your teachers. They know about the material and examination pattern a lot.

Even people who are taking postal coaching should follow this pattern. They should request their parents to organize the test for them every week. By requesting parents, one will put a monitor to himself to adhere to a time table.

How many one has to study: A general prescription is 10 hours a day. One can make an individual judgement with the overall constraint that you have to reach a level of having the ability to write an examination in the material that you have studied. You have to study 9 lessons every month. You divide the time in the ratio of 2:1 for CMP and other subjects.

Preparing a revision notes as you study is important because that will reduce the time spent by you in earlier lessons.

What are the recommended books?

I liked H C Verma for Physics

Dr. Jauhar for Chemistry

For Mathematics, I have Khanna, Dasgupta, Sharma and TMH. I am yet to study and decide which one is the most appropriate one.


Join Orkut Community

IIT-JEE-ACADEMY

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