Claim: Crystal violet, which was important as a topical antiseptic and known as methyl violet 10B, has a molar mass of 407.99 grams per mole.
Evidence: Crystal violet or gentian violet, also known as methyl violet 10B or hexamethyl pararosaniline chloride, is a triarylmethane dye used as a histological stain and in Gram's method of classifying bacteria. Crystal violet has antibacterial, antifungal, and anthelmintic properties and was formerly important as a topical antiseptic. Molar mass 407.99 g·mol