The compound that has the highest melting point amongst the following is: (a) Methane (b) Sodium chloride (c) Ammonia (d) Ethanol

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

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

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.

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.

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]

The diagram given below shows the bonding in the covalent molecule AB2. Which option represents the correct electronic configuration of atoms A and B before combining together to form the above molecule? Option A B (a) 2, 4 2, 8, 6 (b) 2, 4 2, 8, 7 (c) 2, 8 2, 8, 8 (d) 2, 6 2, 8, 7

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

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.

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) 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−