What is baking powder a mixture of?

Baking powder is a mixture of sodium hydrogen carbonate and edible acid-like tartaric acid.

Baking powder

Baking powder is a raising agent that is commonly used in cake-making. It is made from an alkali, bicarbonate of soda, an acid, cream of tartar, and a filler like cornflour or rice flour, which absorbs moisture. The powder is activated when liquid is added, producing carbon dioxide and forming bubbles that cause the mixture to expand.

• Bakers add a small amount of baking soda to the mixture of flour, sugar, eggs, butter and other ingredients in cakes, cookies and other baked goods.
• Sodium bicarbonate also is an active ingredient in antacid products used to relieve heartburn and treat acid indigestion.
• Baking powder is made up of baking soda and acid. Its base is more acidic than baking soda, so it starts working on its own by mixing it in food.