To determine total carbon dioxide in baking powders. Carbon dioxide may be released from various carbonate sources including sodium bicarbonate, potassium bicarbonate, ammonium bicarbonate, calcium carbonate, and sodium carbonate. A strong acid, e.g. sulfuric acid, is required to neutralize carbonate sources. Bicarbonates are added to baking powders to provide carbon dioxide for leavening, and calcium carbonate is added as a diluent, to keep sodium bicarbonate and leavening acid separated. Generally used in combination with starch, calcium carbonate is also a source of calcium for nutritional fortification. This method can be used for single- or double-acting baking powders that contain various leavening ingredients such as sodium aluminum sulfate, sodium acid pyrophosphate, sodium aluminum phosphate, monocalcium phosphate, dimagnesium phosphate, or organic acids.