Question

In a bakery, baking powder was not added while preparing cakes. The cake obtained was hard and small in size. What is the reason for this?

Answer 1

Hint: Chemical leavening agents play a crucial role in baking a cake. They cause the batter to rise by enlarging the bubbles present in it.

Complete step-by-step solution:
Baking powder is a dry chemical leavening agent, made up of an acid, base and a buffering material. This buffering material prevents the reaction of acid and base before their intended use. For instance, corn-starch is a common buffering material.
Most common form of base used is sodium bicarbonate or carbonate \[{\text{NaHC}}{{\text{O}}_{\text{3}}}\], which is also known as baking soda.
The acids used in baking powders are weak acids such as, tartaric acid, monocalcium phosphate, sodium aluminium phosphate, etc.
Chemical reaction of baking soda is –
\[2NaHC{O_3} \to N{a_2}C{O_3} + C{O_2} + {H_2}O\]
Instead of soda, baking powder is preferred to neutralise the base as it has acid along with baking soda, according to the following equation:
\[NaHC{O_3} + {H^ + } \to N{a^ + } + C{O_2} + {H_2}O\]
Sodium bicarbonate in presence of acid when combined with water, breaks down to carbonate and releases carbon dioxide, making the cake rise by creating air bubbles in it. Baking powder increases the volume of the cake and lightens the texture of baked sponge through an acid-base reaction, thus leavening the batter.
That is why, absence of baking powder results in hard and small-sized cakes.

Note: Some good substitutes for baking powder in case not accessible are- buttermilk, plain yoghurt, baking soda with vinegar and lemon juice. They work the same as baking powder.