Give the balanced equation for the action of heat on the following compound:

Washing soda.

The action of heat on washing soda (${\mathrm{Na}}_2{\mathrm{CO}}_3.10{\mathrm{H}}_2\mathrm{O}$):

• Washing soda is chemically known as sodium carbonate decahydrate.
• On heating, washing soda decomposes into sodium carbonate and water.
• This is a decomposition reaction.

Decomposition reaction:

• When the molecules of one substance split into two or more simpler substances, the reaction is called a decomposition reaction.
• These reactions are brought about in the presence of an external agent such as heat, light, and electricity.

The balanced equation is:

$$\begin{gathered} {\mathrm{Na}}_2{\mathrm{CO}}_3.10{\mathrm{H}}_2\mathrm{O}\stackrel{∆}{\to }{\mathrm{Na}}_2{\mathrm{CO}}_3+10{\mathrm{H}}_2\mathrm{O} \\ \mathrm{Sodium}\mathrm{carbonate}\mathrm{Sodium}\mathrm{water} \\ \mathrm{decahydrate}\mathrm{carbonate} \end{gathered}$$