Chemistry - Complete s-block Question with Solution | TestHub

Washing soda, Na₂CO₃.10H₂O, loses 9 water molecules on exposure to air, forming a monohydrate, Na₂CO₃.H₂O. This process is called efflorescence.

The reaction is:

$${\mathrm{Na}}_2{\mathrm{CO}}_3\cdot 10{\mathrm{H}}_2{\mathrm{O}}_{(\mathrm{s})}\stackrel{exposuretoair}{\to }{\mathrm{Na}}_2{\mathrm{CO}}_3\cdot {\mathrm{H}}_2{\mathrm{O}}_{(\mathrm{s})}+9{\mathrm{H}}_2{\mathrm{O}}_{(\mathrm{g})}$$