pyrogallol r trihydroxybenzene

pyrogallol r trihydroxybenzene

a soluble phenol (C6H4 (OH)3) which, in alkaline solution, will absorb oxygen and is used to estimate the volume of oxygen in a gaseous sample.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005