Alum is used in the manufacture of cloth as

Options

A. an oxidant
B. a reductant
C. a drying agent
D. a mordant

Explanation

**Step-by-Step Solution:**

1. **Understanding Alum**: Alum is a chemical compound, specifically potassium aluminum sulfate, with the formula K₂SO₄·Al₂(SO₄)₃·24H₂O. It is commonly used in various applications, including textile manufacturing.

2. **Identifying the Role of Alum in Textile Manufacturing**: In the context of cloth manufacturing, alum is primarily used in the dyeing process. It acts as a mordant.

3. **Defining Mordant**: A mordant is a substance that helps fix dyes onto fabrics. It improves the adherence of the dye to the fabric, ensuring that the color remains vibrant and does not wash out easily.

4. **Benefits of Using Alum as a Mordant**:
- **Improves Washability**: Alum enhances the washability of natural dyes, meaning that the dyed fabric can withstand washing without losing color.
- **Maintains Color Clarity**: It helps in keeping the color clear and bright, preventing it from fading or running.
- **Cost-Effective**: Alum is an inexpensive option compared to other mordants.
- **Safety**: It is considered safe for use in textile applications, posing minimal risk to health.

5. **Conclusion**: Based on the above points, alum is used in the manufacture of cloth as a mordant.

**Final Answer**: Alum is used in the manufacture of cloth as a mordant (Option D).

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