Final answer:
During baking, a decomposition chemical reaction occurs when compounds like those in baking powder break down to produce carbon dioxide gas, which causes bread to rise and become fluffy.
Step-by-step explanation:
One type of chemical reaction found during baking involves the breakdown of compounds to produce gases that cause baked goods to rise, such as bread. This is known as a decomposition reaction, which is a specific type of catabolic reaction where bonds within a larger molecule are broken down, releasing smaller molecules or atoms. A common example of this in baking is the decomposition of sodium hydrogen carbonate (sodium bicarbonate or baking soda) in baking powder.
When baking powder, which contains sodium bicarbonate and usually an acid like sodium aluminum sulfate or sodium acid phosphate, is mixed with water and heated during the baking process, a reaction occurs. This reaction produces carbon dioxide gas (CO₂), water, and other substances. For instance, a reaction with sodium bicarbonate and sodium aluminum sulfate would be: 3NaHCO3 + NaAl(SO4)2 → Al(OH)3 + 2Na₂SO₄ + 3CO₂.
The CO₂ gas released forms bubbles in the dough, causing it to expand and giving the bread its fluffy texture. This process is crucial for the structure and texture of many baked goods and is a core principle in understanding the chemistry of baking.