Question

By writing chemical equation,

Give two examples of direct combination when one compound and one element is involved.

Answer 1

A combination reaction in which two or more substances combine to form single substance under suitable condition.

• Sulphur reacts with oxygen gas to form gaseous sulphur dioxide

Sulphur dioxide is a compound and oxygen is an element they combine to form sulphur trioxide

$\underset{\mathrm{sulphur}\mathrm{dioxide}}{\underset{}{2{\mathrm{SO}}_2\left(\mathrm{g}\right)}}+\underset{\mathrm{oxygen}}{\underset{}{{\mathrm{O}}_2}}\left(\mathrm{g}\right)\rightleftharpoons \underset{\mathrm{sulphur}\mathrm{trioxide}}{\underset{}{2{\mathrm{SO}}_3}}\left(\mathrm{g}\right)$

• Carbon monoxide reacts with oxygen gas to form carbon dioxide.

Carbon monoxide is a compound and oxygen is an element they combine to form carbon dioxide

$\underset{\mathrm{carbon}\mathrm{monoxide}}{\underset{}{2\mathrm{CO}}}\left(\mathrm{g}\right)+\underset{\mathrm{oxygen}}{\underset{}{{\mathrm{O}}_2}}\left(\mathrm{g}\right)\to \underset{\mathrm{carbon}\mathrm{dioxide}}{\underset{}{2{\mathrm{CO}}_2}}\left(\mathrm{g}\right)$