Question

____ dyes are salts of sulfonic or carboxylic acids. They are used to dye fibers with basic groups such as wool, silk and polyamides.

• A. Acid
• B. Methylene blue
• C. Basic
• D. Crystal violet

Hint:

Acid dyes work well on wool and silk fibres.

Answer 1

The Correct Option is A

Concept:
Acid dyes are water-soluble dyes containing acidic groups.
Step 1:
Acid dyes are generally salts of: \[ \text{sulfonic acids or carboxylic acids} \]
Step 2:
They are used for fibres containing basic groups such as:
• Wool
• Silk
• Polyamides
Step 3:

• Methylene blue and crystal violet are specific dyes
• Basic dyes are cationic dyes
Step 4:
Thus correct answer is: \[ \boxed{\text{Acid dyes}} \] \[ \boxed{\text{Correct Option = (1)}} \]