The following table shows electronic configuration: Element Electronic configuration A 2,8,8,2 B 2,6 C 2,8,7 D 2,4 (a) Write the formula of the compound formed between: (i) A and B (ii) D and C (b) Which element exhibits catenation?

Give reasons for the following: (a) Inert gases do not form ions. (b) Covalent compounds have a low melting and boiling point.

X - HCl ⇋ H1+ + Cl- (in solution state) Y - PbBr2 ⇋ Pb2+ + 2Br1- (in molten state) From the above reactions X or Y, identify the reaction which exhibits: (a) electrolytic dissociation (b) ionization

Draw the electron dot structure of: (a) Methane molecule (b) Nitrogen molecule [Atomic number: N = 7, C = 6, H = 1]

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.

Complete the following sentences by choosing the correct answer from the brackets: (a) The salt that can be prepared by Direct Combination is ............... . [FeCl3 / FeCl2] (b) The metallic oxide which can be reduced by using common reducing agents is ............... . [Fe2O3 / Al2O3] (c) The metal nitrate which on thermal decomposition forms a black residue is ............... . [zinc nitrate / copper nitrate] (d) During the electrolysis of copper sulphate solution, if ............... is used as electrodes, the colour of the electrolyte does not fade. [copper / platinum] (e) The process of heating the concentrated ore in a limited supply or absence of air is ............... . [roasting / calcination]

Match the Column A with Column B: Column A Column B (a) Water 1. Lithium (b) Alkali metal 2. Iodine (c) Halogen 3. Covalent compound (d) Calcium oxide 4. Acetic acid (e) Weak acid 5. Ionic compound 6. Sulphuric acid

The following sketch represents the electroplating of an Iron cup with Nickel metal. Study the diagram and answer the following questions: (a) During electroplating the iron cup is placed at the cathode. Why? (b) Name the ion that must be present in the electrolyte. (c) State one condition that is necessary to ensure that the deposit is smooth, firm and even. (d) Write the reaction taking place at the cathode. (e) What change would you observe at the anode?

In a water molecule, the oxygen atom has: (a) One shared pair of electrons (b) Three shared pairs of electrons (c) Two lone pairs of electrons (d) One lone pair of electrons

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

Draw the electron dot structure for the following: (a) Ammonium ion (b) A molecule of nitrogen [At. No.: N=7, H=1]

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)