Write the balanced chemical equations for the following reactions.

(a) Calcium hydroxide + Carbon dioxide ⟶ Calcium carbonate + Water

(b) Zinc + Silver nitrate ⟶ Zinc nitrate + Silver

(c) Aluminium + Copper chloride ⟶ Aluminium chloride + Copper

(d) Barium chloride + Potassium sulphate ⟶ Barium sulphate + Potassium chloride

Write the balanced chemical equation for the following and identify the type of reaction in each case.

(a) Potassium bromide (aq) + Barium iodide (aq) ⟶ Potassium iodide (aq) + Barium bromide (s)

(b) Zinc carbonate (s) ⟶ Zinc oxide (s) + Carbon dioxide (g)

(c) Hydrogen (g) + Chlorine(g) ⟶ Hydrogen chloride (g)

(d) Magnesium (s) + Hydrochloric acid (aq) ⟶ Magnesium chloride (aq) + Hydrogen(g)

Why is respiration considered an exothermic reaction? Explain?

Why are decomposition reactions called the opposite of combination reactions? Write equations for these reactions?