Question

By writing chemical equation

Give two examples of direct combination when two elements are involved

Answer 1

A direct combination reaction is a reaction where two or more elements or compounds combine to form a single product..

• A reaction between calcium and oxygen to form calcium oxide.

$\underset{\mathrm{calcium}}{2\mathrm{Ca}}+\underset{\mathrm{oxygen}}{{\mathrm{O}}_2}\to \underset{\mathrm{Calcium}\mathrm{oxide}}{2\mathrm{CaO}}$

• Reaction of ammonia and hydrogen chloride to produce ammonium chloride.

$\underset{\mathrm{ammonia}}{{\mathrm{NH}}_3\left(\mathrm{g}\right)}+\underset{\mathrm{hydrogenchloride}}{\mathrm{HCl}\left(\mathrm{g}\right)}\to \underset{\mathrm{ammonium}\mathrm{chloride}}{{\mathrm{NH}}_4\mathrm{Cl}\left(\mathrm{s}\right)}$