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本文进一步讨论了室温显色条件,在0.2～0.5N 的硝酸、硫酸、高氯酸中获得基本一致的显色速度。磷酸及磷酸盐妨碍显色,银盐用量由原方法的每25毫升显色液中含硝酸银75毫克降至10毫克。并对反应机理进行讨论,认为中间产物涉及三价银的形成:Ag~++S_2O_8~(2-)=2SO~(2-)_4+Ag~(3+) 5Ag~(3+)+2Mn~(2+)+8H_2O=2MnO_4~-+5Ag~++16H~+
This article further discusses the room temperature color conditions, 0.2 ~ 0.5N nitric acid, sulfuric acid, perchloric acid obtained basically the same color speed. Phosphoric acid and phosphate obstruct the color development. The amount of silver salt is reduced from 75 mg of silver nitrate to 10 mg per 25 ml of color developing solution by the original method. And the reaction mechanism was discussed. It was considered that the intermediate product involved the formation of trivalent silver: Ag ~ + + S_2O_8 ~ (2 -) = 2SO ~ (2 -) _4 + Ag ~ (3 +) 5Ag ~ (3 +) + 2Mn ~ (2 +) + 8H_2O = 2MnO_4 ~ - + 5Ag ~ + + 16H ~ +