confusedWhy on earth is the compound with formula Na2S2O4 called sodium HYDROsulfite when there's no sign of hydrogen anywhere near it? (It's also called sodium dithionate and sodium sulfoxylate, both of which are more sensible names). I'd think it was a typo for sodium hyposulfite if it wasn't so damned prevalent on the web. But sodium hyposulfite appears to be an old name for sodium thiosulphate, Na2S2O3.
Damn you, atoms with too many oxidation states for sensible names to work! (See also: nitrogen).
