NaHCO3 + H+ -> Na+ + CO2 + H2OThe baking powder found in my pantry, as shown in the photograph, is labeled as "Double Acting." Double-acting baking powder is the most common type of baking powder. It contains two acid salts, one of which reacts immediately upon exposure to water, and another that reacts only at the high temperatures found in the baking oven. Cream of tartar (potassium bitartrate, KC4H5O6) and monocalcium phosphate (CaH4P2O8) are the usual low temperature acid salts.[1] The Davis baking powder pictured uses monocalcium phosphate as the low temperature acid salt, and sodium aluminum sulfate as the high temperature acid salt. The inventor of the first useful baking powder was Harvard chemist Eben Norton Horsford, who was the Rumford Professor of the Application of Science to the Useful Arts.[2-3] His professorship was named in honor of the American physicist, Benjamin Thompson, also known as Count Rumford. Thompson is best known for his experiments that demonstrated the mechanical equivalent of heat.
Eben Norton Horsford From his dress, we can surmise that the Harvard classrooms were somewhat chilly. Boston had a record low temperature of -12°F (-24.4°C) in 1951. I wasn't able to find temperature data for Horsford's era. (Via Wikimedia Commons). |