Potash alum is used as a

Options

A. Disinfectant
B. Water softener
C. Mordant in textile industry
D. Fibre in polymer industry

Answer

To determine the uses of potash alum, we can analyze its applications step by step.

### Step-by-Step Solution:

1. **Identify Potash Alum**: Potash alum, chemically known as potassium aluminum sulfate (KAl(SO₄)₂·12H₂O), is a type of double sulfate salt.

2. **Purification of Water**: One of the primary uses of potash alum is in the purification of water. It acts as a coagulant, helping to remove impurities and suspended particles from water, making it safe for drinking.

3. **Tanning**: Potash alum is also used in the tanning of leather. It helps in the process of converting animal hides into leather by stabilizing the proteins in the hides.

4. **Medicine and Cosmetics**: Potash alum has applications in medicine and cosmetics. It is used as an astringent and antiseptic in various medicinal formulations and cosmetic products.

5. **Disinfectant**: Potash alum can be used as a disinfectant due to its antimicrobial properties, making it effective in killing bacteria and other pathogens.

6. **Water Softener**: While potash alum is not primarily a water softener, it can help in the removal of hardness-causing ions in water, thus contributing to water softening indirectly.

7. **Textile Industry**: Potash alum is used as a mordant in the textile industry, which helps in fixing dyes to fabrics.

8. **Polymer Industry**: Potash alum is not used as a fiber in the polymer industry, making this option incorrect.

### Conclusion:
Based on the analysis, potash alum is primarily used in the following ways:
- Purification of water
- Tanning of leather
- Medicine and cosmetics
- As a disinfectant