What’s the difference between baking soda and baking powder, because they are not equally interchangeable? And just because they look similar to flour, does not mean you can substitute either one for the other.
Baking Powder reacts first with liquids and then with heat during baking.
* You can substitute 1/2 teaspoon of cream of tartar and 1/2 teaspoon of baking soda for 1 teaspoon of baking powder.
Baking Soda reacts instantly with liquids and acidic ingredients such as molasses, sour cream and buttermilk. (Baked goods with baking soda should be baked as soon as the liquid is added as possible.
Recipes that generally don’t use baking soda, but instead require baking powder generally have longer baking times. This is because the cream of tartar in baking powder acts as a second leavening agent, and takes over when the baking soda, or sodium bicarbonate, is rendered inactive by long exposure to heat.