... in water, with light nitrogen oxides-like odour. Oxalic acid dihydrate begins to dissociate at temperature over 30 °C. ... quickly, it melts at 101.5 °C,anhydrous oxalic acid melts at 180 °C.Applications:Purifying agent in pharmaceutical ... , it is about 3, 000 times stronger than acetic acid. Its conjugate base, known as oxalate (C2O42-), is a ... products pls feel free to contact with me. Oxalic acid 99.6%