Baking soda causes the cookie to rise. Tiny air bubbles are formed when baking soda comes in contact with liquid and acid. This effect does not last long, so it is important to bake the cookies soon after mixing the ingredients.
Baking powder can be used to replace baking soda in many recipes for cookies. However, more baking powder is required, and its use may affect the taste of the cookies. Baking powder is made by mixing baking soda and cream of tartar together.
Baking soda is a chemical compound that is also known as sodium bicarbonate. It is commercially mined from river basins.