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The element with atomic number 17 is Chlorine with a valency of -1, that is it needs to receive an electron or possibly lose seven electrons to obey the octet rule.

Destructive distillation of a tonne of coal can produce 700 kg of coke, 100 liters of liquor ammonia, 50 liters of coal tar and 400 M\(^3\) of coal gas

A lye is a metal hydroxide traditionally obtained by leaching wood ashes, or a strong alkali which is highly soluble in water producing caustic basic solutions / an alkaline solution that is used to make soaps. "Lye" most commonly refers to sodium hydroxide (NaOH), but historically has been used for potassium hydroxide (KOH).

The reaction of calcium carbide with water, producing acetylene and calcium hydroxide, was discovered by Friedrich Wöhler in 1862. This reaction was the basis of the industrial manufacture of acetylene, and is the major industrial use of calcium carbide.

A Mixture contains two or more constituents which can be easily separated by physical methods. Examples include Air, Soil, Palm oil, Sea water, Blood, Crude oil, etc

500cm\(^3\) of the gas weighed 1.58 : 22400cm\(^3\) of the gas weight [22400 X 1.58g] \div [ 500 ] = 71

Nitrogen(I)Oxide rekindles a brightly glowing splinter but extinguishes a feebly glowing one which is not hot enough to decompose the gas to liberate oxygen

The ammonia molecule has a trigonal pyramidal shape with the three hydrogen atoms and an unshared pair of electrons attached to the nitrogen atom.

The addition of conc HCL makes the solution more acidic and the solution falls below the original value

Chromatography is a method of separating mixtures by using a moving solvent on filter paper. The rate at which each solute moves up the paper depends on how strongly it is absorbed by the paper, and how soluble it is in the solvent.

Deliquescence, the process by which a substance absorbs moisture from the atmosphere until it dissolves in the absorbed water and forms a solution. Deliquescence occurs when the vapour pressure of the solution that is formed is less than the partial pressure of water vapour in the air. A particular example of hygroscopic behavior is deliquescence which is exhibited by many water-soluble solids, including inorganic salts (e.g., calcium chloride).

Helium floats because it is buoyant; its molecules are lighter than the nitrogen and oxygen molecules of our atmosphere and so they rise above it

32g of CUSO\(_4\) liberate 13.0kj of heat Molar mass of CUSO\(_4\) = 160g No. of moles of CUSO\(_4\) = 32g No. of moles = 32(mass) / 160(molar mass) = 0.2 moles i.e 0.2 = 13kj 1 moles = xkj : 65KJ

M Cl % composition 20.22 79.78 Atomic mass 27 35.5 Mole ratio 20.22 79.78 27 35.5 0.75 2.25 Divided 0.75 0.75 1 3 The formula of the Chloride = MCl\(_3\)

4OH ⇒ 2H\(_2\)O + O\(_2\) + 4e- From the equation: 1 mole of Oxygen requires 4e i.e 1 mole of Oxygen requires 4F, where 1F = 96,500 C [ 4 X 96,500 X 0.125 ] \div 1 = 48,250 C