Hydrogenoxalate
Hydrogenoxalate or hydrogen oxalate is an anion with chemical formula HC2O4− or HO2C–CO2−, derived from oxalic acid by the loss of a single proton; or, alternatively, from the oxalate anion C2O42− by addition of a proton.
The name is also used for any salt containing this anion, such as NaHC2O4, KHC2O4, or NH3HC2O4. Hydrogenoxalates may also be called (especially in older literature) binoxalates, acid oxalates, or monobasic oxalates.
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