Baking soda and baking powder are both leavening agents, which are substances used to help baked goods rise.
Baking soda, chemically known as sodium bicarbonate, is a baking ingredient that’s activated by a liquid and an acid to help with leavening, or rising.
Baking powder is a complete leavening agent, meaning it contains both sodium bicarbonate and an acidic ingredient. It’s available as a single- or double-acting agent, though double-acting powders are more widely used.
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