Which of the following is an alternative name for baking soda?

Sodium bicarbonate is an alternative name for baking soda. It is a chemical compound with the formula NaHCO₃, which consists of sodium ions and bicarbonate ions. Sodium bicarbonate serves as a leavening agent in baking by reacting with acids to produce carbon dioxide gas, which causes doughs and batters to rise.

The other substances listed do not serve the same purpose or belong to the same chemical family. Carbon dioxide is a gas produced during the reaction of baking soda with acidic ingredients but is not synonymous with baking soda itself. Potassium bitartrate, also known as cream of tartar, is a byproduct of winemaking and is used in conjunction with baking soda but is distinct from it. Calcium carbonate is a different compound altogether, commonly used as a calcium supplement or a building material, and has no direct relation to the leavening properties of baking soda.