IIT JEE Ch.14. COMPOUNDS OF METALS - Core Points for Revision

JEE Syllabus

Preparation and properties of the following compounds:
Oxides,
peroxides,
hydroxides,
carbonates,
bicarbonates,
chlorides and
sulphates of

sodium,
potassium,
magnesium and
calcium;

Aluminium: alumina, aluminium chloride and alums;

---------------


Sodium Oxide
Sodium oxide has formula Na2O.
It is also called sodium(I) oxide, disodium oxide, sodium monoxide, and soda.

Sodium peroxide
A nearly white compound (Na 2 O 2 ), having vigorous oxidizing properties, and used in bleaching mechanical paper pulps and as a final stage in the bleaching of chemical paper pulps in some multi-stage bleaching sequences.

Sodium hydroxide
sodium hydroxide chemical compound, NaOH, is a white crystalline substance that readily absorbs carbon dioxide and moisture from the air.

Sodium carbonate
Sodium carbonate exists as anhydrous (Na2CO3) and also as hydrated salt. The decahydrated salt (Na2CO3.10H2O) is known as washing soda while the anhydrous salt is called soda ash.


Sodium Bicarbonate NaHCO-3
Sodium Bicarbonate, commonly called baking soda, is a white odourless, crystalline solid, completely soluble in water but slightly soluble in ethanol. It is the mildest of all sodium alkalis.



Sodium chloride
Sodium chloride (NaCl) or common salt is an ionic crystal consisting of equal numbers of sodium and chlorine atoms and is an essential component in the human diet, being found in blood sweat and tears.

Sodium sulphate

FORMULA Na2SO4
Sodium sulfate is a white, orthorhombic crystalline solid at room temperatures ( a monoclinic structure at > 100 C, a hexagonal structure at > 250C).


Potassium Oxide
Formula as commonly written: K2O

Physical properties
• Colour: yellowish white to grey
• Appearance: crystalline solid

Potassium peroxide
K2O2

Potassium hydroxide
Potassium Hydroxide, commonly called caustic potash with formula KOH, is a caustic compound of strong alkaline chemical dissolving readily in water, giving off much heat and forming a caustic solution.

Potassium carbonate
Potassium carbonate is a white salt, soluble in water (insoluble in alcohol), which forms a strongly alkaline solution.

Potassium bicarbonate
Potassium bicarbonate (also known as potassium hydrogen carbonate or potassium acid carbonate), is a colorless, odorless, slightly basic, salty substance.

Potassium chloride - KCl
Potassium chloride is also commonly known as "Muriate of Potash".

Potassium sulphate
Potassium sulfate (K2SO4) (also known as potash of sulfur) is a non-flammable white crystalline salt which is soluble in water. The chemical is commonly used in fertilizers, providing both potassium and sulfur.




Magnesium Oxide
Magnesium oxide

Roasting either magnesium carbonate or magnesium hydroxide produces the oxygen compound magnesium oxide, commonly called magnesia, MgO, a white solid used in the manufacture of high-temperature refractory bricks, electrical and thermal insulators, cements, fertilizer, rubber, and plastics. It is used medically as a laxative.


Magnesium peroxide
Magnesium peroxide is a fine powder peroxide with a white to white-off color.

Magnesium hydroxide
Magnesium hydroxide, Mg(OH)2, is a white powder produced in large quantities from seawater by the addition of milk of lime (calcium hydroxide).

Magnesium carbonate
Magnesium carbonate, MgCO3, occurs in nature as the mineral magnesite and is an important source of elemental magnesium. It can be produced artificially by the action of carbon dioxide on a variety of magnesium compounds.

Magnesium bicarbonate
Mg(HCO3)2
Magnesium bicarbonate + Lime → Calcium carbonate + Magnesium carbonate + Water
Mg(HCO3)2 + Ca(OH)2 → CaCO3 + MgCO3 + 2H2O

Magnesium chloride
The action of hydrochloric acid on magnesium hydroxide produces magnesium chloride, MgCl2, a colourless, deliquescent (water-absorbing) substance employed in magnesium metal production, in the manufacture of a cement for heavy-duty flooring, and as an additive in textile manufacture.

Magnesium sulphate
Magnesium sulfate, MgSO-4, is a colourless, crystalline substance formed by the reaction of magnesium hydroxide with sulfur dioxide and air.


Calcium Oxide CaO
Calcium oxide is commonly known as quicklime, and is a material of primary importance in the building industry.

Calcium peroxide
Calcium peroxide (CaO2) is a solid peroxide with a white or yellowish color.

Calcium hydroxide
Calcium hydroxide (Ca(OH)-2)

Calcium hydroxide in solid powdered form is called slaked lime. A suspension of slaked lime in water is called milk of lime.

Calcium carbonate CaCO3
Calcium carbonate occurs abundantly as dolomite, MgCO3.CaCO3, a mixture of calcium and magnesium carbonates.

Calcium bicarbonate
Calcium bicarbonate (Ca(HCO3)2), also called calcium hydrogen carbonate, does not refer to a known solid compound; it “exists” only in a solution containing the ions calcium Ca^2+, dissolved carbon dioxide CO2, bicarbonate HCO3–, and carbonate CO3^2–.

Calcium chloride
Calcium chloride (CaCl2) is an ionic compound of calcium and chlorine.
It can be produced directly from limestone, but large amounts are also produced as a by-product of the Solvay process.

Calcium sulphate (CaSO4)
Calcium sulphate can be obtained by heating gypsum above 200°C.


Compounds of Aluminium: alumina, aluminium chloride and alums;

Aluminium oxide(Al2O3), also known as alumina, is the main component of bauxite, the principal ore of aluminium.

Aluminium chloride (AlCl3) is manufactured on a large scale by the exothermic reaction of aluminium metal with chlorine or hydrogen chloride.

Alum is a salt that in chemistry is a combination of an alkali metal, such as sodium, potassium, or ammonium and a trivalent metal, such as aluminum, iron, or chromium.

The most common form, potassium aluminum sulfate, or potash alum, is one form that has been used in food processing.