Question

Sunita was learning to bake cakes. She added the ingredients according to the recipes and placed
them in the oven. When the cake was ready she took it out from the oven. She was surprised as the
cake was hard instead of soft and fluffy.
(a) What is the probable reason that the cake was not fluffy?
(b) What ingredient did she miss adding while preparing the cake?
(c) Write a chemical reaction to show how this ingredient makes the cake
fluffy?
(d)What is the chemical constituent of this ingredient?

Answer 1

Dear student,

(i) Baking powder is added to the flour while preparing the dough for the cakes. When baking powder mixes with water, then the sodium hydrogen carbonate reacts with tartaric acid to evolve carbon dioxide gas which gets trapped in the wet dough and bubbles out slowly making the cake to rise and hence 'soft and spongy', most probably she didn't added backing powder

(ii) The baker had forgotten to add baking powder. Baking powder is a mixture of baking soda (sodium hydrogen carbonate) and a mild edible acid such as tartaric acid.

(iii) On heating the sodium bi carbonate the following changes taken place :
NaHCO₃ + H⁺ → CO₂ + H₂O + Sodium salt of acid$\uparrow$
Evolution of carbon di oxide gas makes small pore in the food items in which air is filled and make them fluffy
the effect of the formation of washing soda while heating of baking soda the citric acid is added as it combines with the sodium carbonate and forms salt , water and more carbon dioxide

(iv)Baking powder is a mixture of baking soda (NaHCO₃) and a mild edible acid such as tartaric acid.
Regards