Which one is an acidic dye ?

Options

A. Methyl orange
B. Methyl red
C. Phenolphthalein
D. All of these

Answer

A

Explanation

Acid dyes are characterised by the presence of –COOH, `–SO_3 H` or Phenolic group. They are applied in the presence of acidic solution. They are usually applied to Wool, Silk, and Nylon. They have affinity for cotton. Common examples are Orange I, Orange II, Methyl orange etc.