Sodium bicarbonate is a leavening agent that's commonly used in baking. Although inactive in its dry form, mixing it with an acid and liquid causes a chemical reaction that releases a gas. This gas, carbon dioxide, produces bubbles that expand when the mixture is heated. It is important to place cake mixture in the oven while the bubbles are still active, or the cake will not rise. Baking soda is different in composition from baking powder because baking soda is pure sodium bicarbonate, while baking powder is a combination of sodium bicarbonate, cream of tartar and starch. Cream of tartar is an acid, meaning that baking powder only requires the addition of liquid for its activation. Baking soda is used in recipes that already include an acidic ingredient, such as yogurt, milk, honey or lemon juice.
The use of sodium bicarbonate is not confined to baking. In medicine, it is defined as an antacid and is recommended for the relief of heartburn and indigestion. Baking soda is also gaining popularity as a cleaner and deodorizer around the home, especially due to the rising awareness of pollution and the effects of harmful chemicals to health.Learn more about Atoms & Molecules