Question

Give one example in each case:

A basic oxide which is soluble in water.

Answer 1

A basic oxide that is soluble in water:

• Barium oxide ($\mathrm{BaO}$) is an example of a basic oxide that is soluble in water.
• Barium is a meta and oxides of most metals are basic in nature.
• ${\mathrm{Ba}}^{2+}$is a large cation and ${\mathrm{O}}^{2-}$ is a small anion but the size compatibility of ${\mathrm{Ba}}^{2+}$and ${\mathrm{O}}^{2-}$ is not so high, thus Barium oxide ($\mathrm{BaO}$) is unstable.
• The lattice energy released during its formation is also not very high.
• So this lattice energy can be easily overcome by the hydration energy of the ions.
• Therefore, $\mathrm{BaO}$ is soluble in water.

Hence, an example of basic oxide is soluble in water is Barium oxide ($\mathrm{BaO}$).