Complete the following sentences by choosing the correct option from the brackets: (a) The oxide that dissolves in caustic potash (KOH) is ............... . [ZnO / CuO] (b) The reaction that takes place at the anode during the electrolysis of molten lead bromide is ............... . [2Br − 2e− ⟶ 2Br− / 2Br− − 2e− ⟶ Br2] (c) The volume occupied by 8 grams of oxygen gas at STP is ............... litres. [5.6 / 8.96] [Atomic weight of O = 16] (d) ............... does not give hydrogen gas when it reacts with cold and very dilute nitric acid. [Cu / Mn] (e) ............... is a polar covalent compound. [HCl / CCl4]

Identify the following terms / compounds: (a) A compound which reacts with water to give acetylene gas. (b) The gas evolved when sodium propanoate is heated with soda lime. (c) A reddish-brown precipitate formed when ferric chloride solution reacts with an alkali. (d) A pair of electrons present in an atom which is not shared with any other atom during bond formation. (e) The relative molecular mass of a substance expressed in grams.

5.6 litres of gas Z weighs 32 g at STP. What is the molecular weight and vapour density of Z?

Equal volumes of ammonia gas and chlorine gas are kept in two different containers under the same conditions of temperature and pressure. Find the number of molecules contained in chlorine gas when the mass of ammonia is 34 g. [Atomic weight: Cl=35.5, H=1, N=14]

Ethane burns in oxygen according to the chemical equation: 2C2H6 + 7O2 → 4CO2 + 6H2O If 80 ml of ethane is burnt in 300 ml of oxygen, find the composition of the resultant gaseous mixture when measured at room temperature.

Calculate: (a) The percentage of phosphorus in the fertilizer super phosphate Ca(H2PO4)2 correct to 1 decimal point. (b) Write the empirical formula of C8H18 [At. Wt. H=1, P=31, O=16, Ca=40]

Calcium carbonate reacts with dilute hydrochloric acid as given below: (a) What is the mass of 5 moles of calcium carbonate? (Relative molecular mass of calcium carbonate is 100) (b) How many moles of HCl will react with 5 moles of calcium carbonate? (c) What is the volume of carbon dioxide liberated at S.T.P. at the same time?

Define / State: (a) Electronegativity. (b) Gay-Lussac’s law of combining volumes.

State the terms for the following: (a) The group obtained by removing one hydrogen atom from the parent alkane. (b) Two metal plates or wires through which the current enters and leaves the electrolytic cell. (c) The amount of substance which contains the same number of units as the number of atoms in carbon-12. (d) The tendency of an atom to pull a shared pair of electrons towards itself in a compound. (e) The formula which represents the simplest ratio between the atoms of elements present in a compound.

Arrange the following according to the instructions given in brackets: (a) C2H2, C3H6, CH4, C2H4 (In the increasing order of the molecular weight) (b) Cu2+, Na+, Zn2+, Ag+ (The order of Preferential discharge at the cathode)

State the terms/process for the following: (a) The energy released when an atom in the gaseous state accepts an electron to form an anion. (b) Tendency of an element to form chains of identical atoms. (c) The name of the process by which Ammonia is manufactured on a large scale. (d) A type of salt formed by partial replacement of hydroxyl radicals with an acid radical. (e) The ratio of the mass of a certain volume of gas to the same volume of hydrogen measured under the same conditions of temperature and pressure.

(a) State Avogadro’s Law. (b) Define Co-ordinate bond.