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Science

Cooking food and additives

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Baking powder

Baking powder is used for baking cakes. It contains sodium hydrogencarbonate, which breaks down when heated to form carbon dioxide gas. The carbon dioxide helps to make the cake mixture rise, so that it is light and fluffy.

Here are the equations for the reaction:

sodium hydrogencarbonate → sodium carbonate + carbon dioxide + water

2NaHCO3 → Na2CO3 + CO2 + H2O

sodium hydrogencarbonate is heated and passed through limewater, which turns cloudy

Thermal decomposition of sodium hydrogencarbonate

Testing for carbon dioxide

Carbon dioxide can be detected using a simple laboratory test. Limewater turns cloudy white when carbon dioxide is bubbled through it.

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Back to Carbon chemistry index

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