Question

Write the reaction of any three metal oxides with water.

Answer 1

Metal oxides:

• They are the chemical compounds formed from metal and $\mathrm{Oxygen}$.
• Based on their acid-base characteristics, they are classified into acidic oxides, basic oxides, neutral oxides, and amphoteric oxides.

Acidic oxides:

• Acidic oxides are the oxides of nonmetal.
• They dissolve in water to form acids.
• Acidic $\mathrm{Sulphur}\mathrm{dioxide}\left({\mathrm{SO}}_2\right)$ reacts with water$\left({\mathrm{H}}_2\mathrm{O}\right)$ to form$\mathrm{Sulphurous}\mathrm{acid}\left({\mathrm{H}}_2{\mathrm{SO}}_3\right)$.

$\underset{\mathrm{Sulphur}\mathrm{dioxide}}{{\mathrm{SO}}_2\left(\mathrm{s}\right)}+\underset{\mathrm{Water}}{{\mathrm{H}}_2\mathrm{O}}\left(\mathrm{l}\right)\to \underset{\mathrm{Sulphrous}\mathrm{acid}}{{\mathrm{H}}_2{\mathrm{SO}}_3\left(\mathrm{aq}\right)}$

• Similarly $\mathrm{Carbon}\mathrm{dioxide}\left({\mathrm{CO}}_2\right)$ reacts with water$\left({\mathrm{H}}_2\mathrm{O}\right)$ to form$\mathrm{Carbonic}\mathrm{acid}\left({\mathrm{H}}_2{\mathrm{CO}}_3\right)$.

$\underset{\mathrm{Carbon}\mathrm{dioxide}}{{\mathrm{CO}}_2\left(\mathrm{g}\right)}+\underset{\mathrm{Water}}{{\mathrm{H}}_2\mathrm{O}}\left(\mathrm{l}\right)\to \underset{\mathrm{Carbonic}\mathrm{acid}}{{\mathrm{H}}_2{\mathrm{CO}}_3\left(\mathrm{aq}\right)}$

Basic oxides:

• Basic oxides are the oxides of metal.
• They dissolve in water to form Bases.
• Basic $\mathrm{Calcium}\mathrm{oxide}\left(\mathrm{CaO}\right)$ react with water $\left({\mathrm{H}}_2\mathrm{O}\right)$ to form the base$\mathrm{Calcium}\mathrm{hydroxide}$.

$\underset{\mathrm{Calcium}\mathrm{oxide}}{\mathrm{CaO}\left(\mathrm{s}\right)}+\underset{\mathrm{Water}}{{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}\to \underset{\mathrm{Calcium}\mathrm{hydroxide}}{\mathrm{Ca}{\left(\mathrm{OH}\right)}_2}$

• Similarly $\mathrm{Sodium}\mathrm{oxide}\left({\mathrm{Na}}_2\mathrm{O}\right)$ react with water $\left({\mathrm{H}}_2\mathrm{O}\right)$ to form the base$\mathrm{Sodium}\mathrm{hydroxide}$.

$\underset{\mathrm{Sodium}\mathrm{oxide}}{{\mathrm{Na}}_2\mathrm{O}\left(\mathrm{s}\right)}+\underset{\mathrm{Water}}{{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}\to \underset{\mathrm{Sodium}\mathrm{hydroxide}}{2\mathrm{Na}\mathrm{OH}}$