Sodium saccharin
Formula: C7H4NNaO3S·?H2O
Saccharin is the first successful chemical sugar substitute; it gained its popularity during the time of WWII and is still in use nowadays, though to a much lesser extent: there are tastier and safer substitutes now. Strictly speaking, saccharin is a weak acid, that is almost insoluble in water. Soluble saccharin is its sodium salt: sodium saccharinate.
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