Crystal Violet Solution

Dissolve 0.5 g of crystal violet in anhydrous acetic acid and dilute to 100 mL with the same solvent.

Test for sensitivity To 50 mL of anhydrous acetic acid add 0.1 mL of the crystal violet solution. On addition of 0.1 mL of 0.1 M perchloric acid the bluish-purple solution turns bluish-green.