40g - 490g (1.4 - 17.2oz)CITRIC ACID. You can make your own bath bombs—fizzy, effervescent bath soap/salt—by using citric acid. The “Alka Seltzer-like” fizzy effect is caused by the citric acid reacting with the water and other ingredients of the bomb, such as baking soda, witch hazel and fragrances.
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