Question

Which gas is evolved during baking that makes the cake light and fluffy? Write a balanced reaction.

Answer 1

1. The gas which is evolved / liberated during baking that makes the cake light and fluffy is Carbon dioxide (${\mathrm{CO}}_2$) gas.
2. Sodium bicarbonate (Baking soda) is used in small amount in making bread and cake.
3. When we heat Sodium bicarbonate(${\mathrm{NaHCO}}_3$) which is the main ingredient of Baking , it decomposes to Sodium carbonate(${\mathrm{Na}}_2{\mathrm{CO}}_3$) and releases Water(${\mathrm{H}}_2\mathrm{O}$) with Carbon dioxide(${\mathrm{CO}}_2$) gas.
4. Baking powder(Sodium bicarbonate) is mixed with the flour, when water is added to this flour to make dough, Baking powder undergoes a chemical reaction during which Carbon dioxide gas is produced.
5. The Carbon dioxide gas which gets trapped into the dough and bubbles out that causes the cake to rise making it light, soft, spongy and fluffy.
6. The balanced chemical reaction can be given as: $$\begin{gathered} 2{\mathrm{NaHCO}}_3\left(\mathrm{s}\right)\to {\mathrm{Na}}_2{\mathrm{CO}}_3\left(\mathrm{s}\right)+{\mathrm{H}}_2\mathrm{O}\left(\mathrm{g}\right)+{\mathrm{CO}}_2\left(\mathrm{g}\right) \\ (\mathrm{Sodium}\mathrm{bicarbonate})(\mathrm{Sodium}\mathrm{carbonate})\left(\mathrm{Water}\right)(\mathrm{Carbon}\mathrm{dioxide}) \end{gathered}$$.