Bromocresol Green Solution

Dissolve 50 mg of bromocresol green in 0.72 mL of 0.1m sodium hydroxide and 20 mL of ethanol (96%). After solution is effected add sufficient water to produce 100 mL.

Complies with the following tests.

Sensitivity A mixture of 0.2 mL of the solution and 100 mL of carbon dioxide-free water is blue. Not more than 0.2 mL of 0.02m hydrochloric acid VS is required to change the colour of the solution to green.

Colour change pH 3.6 (yellow) to pH 5.2 (blue).