Question

What is the composition of baking powder? How does it work?

Short answer

Answer: Baking powder is composed of a weak acid and a weak base, most commonly sodium bicarbonate and one or more weak acids like cream of tartar or mono-calcium phosphate. Its purpose in baked goods is to act as a leavening agent, helping the dough rise by producing carbon dioxide gas when mixed with moisture, creating bubbles and resulting in a light and fluffy texture.

Step-by-step solution

Ingredients of Baking Powder

Baking powder is composed of a weak acid and a weak base. The most common ingredients found in baking powder are sodium bicarbonate (NaHCO3), a weak base, and one or more weak acids such as cream of tartar (KC4H5O6) or mono-calcium phosphate (Ca(H2PO4)2).

Purpose of Baking Powder

Baking powder is used in recipes as a leavening agent to make baked goods rise. This is done by producing carbon dioxide (CO2) gas, which creates bubbles in the dough, making it expand and become light and fluffy.

Activation of Baking Powder

When baking powder is mixed with moisture from the recipe ingredients, the weak acid and weak base react with each other to produce carbon dioxide (CO2) gas. The reaction can be represented as: NaHCO3 (s) + H+ (aq) -> CO2 (g) + H2O (l) + Na+ (aq)

Double-acting Baking Powder

Double-acting baking powder contains two types of acids: one that reacts with water at room temperature and another that reacts with heat during baking. This means that some CO2 gas is released when the batter is initially mixed, and then more CO2 gas is released during the baking process. This ensures a more even rise and a better texture in the finished product.

Importance of Proper Measurement

It is essential to measure baking powder accurately in a recipe. Too little baking powder may result in a dense and heavy texture, while too much may cause the baked goods to rise too quickly and then collapse. Follow the recipe's instructions carefully and always use the correct measurements for best results.