Dimethyl Yellow Solution

A 0.2% w/v solution of dimethyl yellow in ethanol (90%).

Complies with the following test.

Sensitivity A solution containing 2 g of ammonium chloride in 25 mL of carbon dioxide-free water to which is added 0.1 mL of the dimethyl yellow solution is yellow. Not more than 0.10 mL of 0.1m hydrochloric acid VS is required to change the colour of the solution to red (pH range, 2.8 to 4.6).