Write the balanced chemical equations for the following reaction:

Aluminium + copper chloride $\to$Aluminium chloride + copper

Balance the following equation by identifying the name of the missing molecule:

Calcium hydroxide $+$ _____ $\to$ Calcium carbonate$+$Water

Correct and balance the following equation:

$\mathrm{N} + \mathrm{H}\to {\mathrm{NH}}_3$

Write a complete balanced equation for the following reaction:

Sulphur dioxide (gas) + Oxygen (gas) $\to$Sulphur trioxide (gas)