Question

A lab technician was told to prepare ammonia in his lab. What reactants should he use?

• A. $Ca(OH{)}_2$ and $N{H}_{4}Cl$
• B. $Ca$ and $N{H}_{4}Cl$
• C. $Ca$ and $N{H}_{4}OH$
• D. $Na$ and $N{H}_{4}Cl$

Answer 1

The correct option is A

$Ca(OH{)}_2$ and $N{H}_{4}Cl$

When a mixture of $Ca(OH{)}_2$ and $N{H}_{4}Cl$ is heated, the products formed are $N{H}_3$ gas, $CaC{l}_2$ and water vapour. Ammonia gas is lighter than air, hence it is collected by the downward displacement of air. Because it is highly soluble in water it cannot be collected over it.

$Ca(OH{)}_2+2N{H}_{4}Cl⟶2N{H}_3+2H_{2}O+CaC{l}_2$