Write balanced chemical equations for the following reactions: (2013)

(a) dilute sulphuric acid reacts with aluminium powder

(b) dilute hydrochloric acid reacts with sodium carbonate

(c) Carbon dioxide is passed through lime water.

Describe and activity to show decomposition reaction in which light is used to decompose a reactant. Write chemical equation of the reaction and state its one use. (2012)

(a) What is meant by balanced chemical equation? Why chemical equations are balanced?

(b) Balance the chemical equation given below:

Al₂O₃ + NaOH → NaAlO₂ + H₂O (2013)

Solid calcium oxide was taken in a container and water was added slowly to it.

(i) State two observations made in the experiment.

(ii) Write the balanced chemical equation of this reaction. (2013)

Mention the rules for writing a chemical equation illustrating with the help of example. (2013)