Baking powder is a leavening agent used in baking. It is a dry chemical that, when combined with moisture and heat, releases carbon dioxide gas. This gas causes the batter or dough to rise, resulting in a light and fluffy texture. Baking powder is typically made from a combination of sodium bicarbonate, an acid (such as cream of tartar), and a starch (such as cornstarch).
It is important to check the baking powder before using it to ensure that it is still active. Inactive baking powder will not produce the desired rise in your baked goods. To check the baking powder, combine 1 teaspoon of baking powder with 1/2 cup of hot water. If the mixture bubbles vigorously, the baking powder is still active. If there is no reaction, the baking powder is inactive and should be discarded.