Hypo is not used in

Options

A. bleaching industry
B. volumetric analysis for determining iodine
C. photography
D. cyanide process for recovery of Ag from argentite ore

Answer

To solve the question "Hypo is not used in," we need to analyze the uses of hypo, which is sodium thiosulfate (Na2S2O3), in various industries. Here’s a step-by-step breakdown:

### Step 1: Identify what hypo is
Hypo is the common name for sodium thiosulfate, which has the chemical formula Na2S2O3.

**Hint:** Remember that hypo is often used in various chemical processes, and knowing its chemical formula can help you understand its reactions.

### Step 2: Explore the uses of hypo
1. **Bleaching Industry**: Hypo is used to neutralize excess chlorine in bleaching processes. The reaction involves sodium thiosulfate reacting with chlorine to form sodium bisulfate and hydrochloric acid.

**Hint:** Think about how hypo can help in processes that involve chlorine, which is a common bleaching agent.

2. **Volumetric Analysis for Iodine**: Hypo is used in titrations to determine the concentration of iodine. The reaction involves sodium thiosulfate reacting with iodine to form sodium tetrathionate and sodium iodide.

**Hint:** Consider how hypo can be useful in quantitative analysis where iodine is involved.

3. **Photography**: In the photographic industry, hypo is used to fix photographs by reacting with excess silver bromide, making it soluble.

**Hint:** Recall that hypo can help in processes that involve silver compounds, especially in photography.

### Step 3: Identify where hypo is not used
The question asks where hypo is not used. The options provided include:
- Bleaching industry
- Volumetric analysis for determining iodine
- Photography
- Cyanide process for recovery of silver from Argentite ore

From our analysis:
- Hypo is used in the bleaching industry.
- Hypo is used in volumetric analysis for iodine.
- Hypo is used in photography.
- **Hypo is not used in the cyanide process for recovery of silver from Argentite ore.**

### Conclusion
The correct answer to the question "Hypo is not used in" is the cyanide process for recovery of silver from Argentite ore.

**Final Answer:** Hypo is not used in the cyanide process for recovery of silver from Argentite ore.