Determination of hydroxyl radicals with salicylic acid in aqueous nitrate and nitrite solutions

Xi Yang1, Man-jun Zhan, Ling-ren Kong

  • 1State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093, China. yangxi@nju.edu.cn

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Nitrous acid, a weak acid, is prepared in situ via the reaction of sodium nitrite with a strong acid under cold conditions. This nitrous acid prepared in situ reacts with primary arylamines to form arenediazonium salts. Such reactions are known as diazotization reactions. As shown in Figure 1, the formation of arenediazonium salts begins with the decomposition of nitrous acid in an acidic solution to give nitrosonium ions.