Give one example in each case where supplying energy [given below] is necessary for a chemical reaction.

(a) Heat energy

(b) Light energy

(c) Electrical energy

(d) Pressure

(e) Catalyst

Representation of the results of a chemical change – is a chemical equation.

For the equation: FeCl₃ + 3NH₄OH ⟶ 3NH₄Cl + Fe(OH)₃ ↓

Answer the following:

(a) Write the word equation for the above molecular equation.

(b) Is the equation given above a balanced equation. Give reasons.

(c) Name the reactants and the products in the above equation.

(d) What is the indications of the arrow between the reactants and the products and of the arrow pointing downwards at the end.

Select the correct answer from A, B, C, D and E for each statement given below:

A: Hydrogen

B: Copper [II] oxide

C: Oxygen

D: Copper [II] hydroxide

E: Ammonia

1. The black residue obtained on heating copper carbonate.

2. The basic gas obtained when two gases react in presence of a catalyst and the reaction is exothermic.

3. The gas obtained when potassium chlorate is heated in the presence of a catalyst.

4. The pale blue precipitate obtained when copper [II] sulphate reacts with sodium hydroxide.

5. The gas which reacts with oxygen to give a neutral liquid.

Give a word equation for each of the following reactions.

1. Two solids which combine on heating, to give a liquid.

2. Two gasses which combine to give a solid.

3. A compound which on heating shows – color change from brown to yellow.

4. A salt which reacts with ammonium hydroxide to give a reddish-brown precipitate.

5. An exothermic reaction where both the reactants are gases, one of which is oxygen.