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

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.

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

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

Give a reason for each: (a) Ionisation potential decreases down a group. (b) Ionic compounds do not conduct electricity in the solid state.

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

Fill in the blanks by choosing the correct answer from the bracket: (a) Carbon tetrachloride is a ............... [polar / non-polar] covalent molecule. (b) During electrolysis of acidulated water, the gas liberated at the anode is ............... [oxygen / hydrogen].

Choose the answer from the list which fits in the description: [CCl4, PbO, NaCl, CuO, NH4Cl] (a) A compound which undergoes thermal dissociation. (b) An amphoteric oxide. (c) A compound which is a non-electrolyte.

Match the Column A with Column B: Column A Column B (a) Sodium chloride 1. has two shared pair of electrons (b) Methane 2. has high melting and boiling points (c) Hydrogen chloride gas 3. a greenhouse gas (d) Oxidation reaction 4. has low melting and boiling points (e) Water 5. Zn − 2e− ⟶ Zn2+ 6. S + 2e− ⟶ S2−

Fill in the blanks with the choices given in the brackets: (a) Metals are good ............... [oxidizing agents /reducing agents] (b) Non-polar covalent compounds are ............... [good / bad] conductors of heat and electricity. (c) Higher the pH value of a solution, the more is ............... [acidic / alkaline] it is. (d) ............... [Silver chloride / Lead chloride] is a white precipitate that is soluble in excess of Ammonium hydroxide solution. (e) Conversion of ethene to ethane is an example of ............... . [hydration / hydrogenation]

Element A belongs to group 15 and period 2 of the Periodic Table. (a) Identify the element A. (b) Write the formula of the compound formed when element A combines with hydrogen. (c) Draw the dot (•) and cross (×) structure of the compound formed in (b) above.