0-Tolidine hydrochloride

Preparation 1.35 g o-tolidine-hydrochloride is dissolved in 500 cm distilled water, and a mixture of 350 cm distilled water and 150 cm concentrated hydrochloric acid is added to it. The solution can be stored for 6 months in the dark. 

For absorption-tube detection of trichloroethylene in air two tubes were recommended, the first filled with silica gel impregnated with potassium permanganate and orthophosphoric acid (in which chlorine is set free), and the second filled with silica gel impregnated with o-tolidine hydrochloride (for detection of the liberated chlorine) (25). 

Cl 37100. See 2-Methyl-4-nitroaniline Cl 37105. See 2-Methyl-5-nitroaniline Cl 37107. See p-Toluidine Cl 37110. See 3-Nitro-p-toluidine Cl 37115. See o-Anisidine hydrochloride Cl 37130. See 2-Methoxy-5-nitroaniline Cl 37225. See Benzidine Cl 37230. See o-Tolidine Cl 37235. See Dianisidine Cl 37240. See N-Phenyl-p-phenylenediamine Cl 37500. See P-Naphthol Cl 40000. See Direct yellow 11 Cl 40002 Cl 40003. See 4,4 -Diaminostilbene-2,2 -disulfonic acid Cl 40645. See Sodium-2-(4-styrvl-3-sulfophenyl)-2H-naphtho-(1,2-d)-triazole Cl 40800... 

Titration mixture (residual chlorine in water analysis). Prepare 1 L of dilute HCl (100 mL of HCl (sp. gr. 1.19) in sufficient distilled water to make 1 L). Dissolve 1 g of o-tolidine (3,3 -di-methylbenzidine, CAS No. 119-93-7) in 100 mL dilute hydrochloride, stir well and dilute to 1 L using dilute HCl solution. 

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