About 25% of produced oxalic acid will be used as a mordant in dyeing processes. It is also used in bleaches, especially for pulpwood, and for rust removal and other cleaning, in baking powder, and as a third reagent in silica analysis instruments.
Oxalic acid, H2C2O4 is a colourless crystalline dicarboxylic acid. It produces a colourless solution on dissolving in water. If we consider the acid strength, it is a much stronger acid than acetic acid. Oxalic acid is a reducing agent and its conjugate base is called as oxalate (C2O4 2-).