A mixture of powdered compounds added to dough or cake mixture to make it rise in cooking. it is used as a substitute for yeast in bread making. baking powder consist of a source of carbon di oxide, such as sodium bi carbonate or ammonium bi carbonate and an acidic substance such as calcium hydrogenphosphate,cream of tartar in the hot wet mixture, the acid releases bubbles of carbon dioxide gas from the bicarbonates which make the mixture rise.
