Question

How would you distinguish between baking powder and washing soda by heating?

Answer 1

• The chemical formula of baking powder is sodium hydrogencarbonate (NaHCO₃).
• Whereas, that of washing soda is sodium carbonate (Na₂CO₃.10H₂O) Sodium hydrogencarbonate on heating gives CO₂ gas which will turn lime water milky whereas no such gas is obtained from sodium carbonate.

\(2NaHCO_3 \overset{Heat}\rightarrow Na_2CO_3+H_2O+CO_2\)

\(Na_2CO_3.10H_2O \overset{Heat}\rightarrow Na_2CO_3+10H_2O\)