What is a white crystalline neutral substance (C2O2(NH2)2) obtained by treating ethyl oxalate with ammonia. It is the acid amide of oxalic acid. Formerly called also oxalamide called?

oxamide — A white crystalline neutral substance (C2O2(NH2)2) obtained by treating ethyl oxalate with ammonia. It is the acid amide of oxalic acid. Formerly called also oxalamide. (Webster's 1913.)

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