Is this accurate information?
Sodium Sulfite may be easily prepared from Sodium Metabisulfite by first dissolving the latter in an excess of water, then adding an amount of Sodium Hydroxide that is equimolar to the formed Sodium Bisulfite. This solution may then be evaporated to obtain crystalline Sodium Sulfite, or used as-is.
Na2S2O5 + H2O = 2(NaHSO3)
NaHSO3 + NaOH = Na2SO3 + H2O
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