Note 564 — Chapter XV · OXIDATION AND REDUCTION. II. OXIDATION BY OXYGEN, PERMANGANATES, ETC.; OXIDATION OF ORGANIC COMPOUNDS
Reading edition
According to the theory, that arsenic acid is an oxidizing agent because it gives up oxygen of a definite pressure, this pressure would be the more effective, the more completely the opposing hydroxide-ion is suppressed by added acid (p. 280; see also p. 272, on the action of ferro-ion on silver-ion in the presence and in the absence of fluorides).