Baking soda, also known as sodium bicarbonate, is widely used in baking. Baking soda is a leavening agent used in baked goods like cakes, muffins, and cookies. Sodium bicarbonate commonly known as baking soda or bicarbonate of soda, is a chemical compound with the formula NaHCO3. Aka bicarbonate of soda or sodium bicarbonate. Baking soda is sodium bicarbonate that is generally used in baked goods.