Original: Pure , water-free acetic acid ( glacial acetic acid ) is a colourless liquid that absorbs water from the environment ( hygroscopy ) , and freezes at 16.5 C ( 62 F ) to a colourless crystalline solid .
Simplified: Its melting point is 16.5 C ( 61.6 F ) and boiling point is 118.1 C ( 244.5 F ) .