Trihydroxybenzene, a developer in photography is popularly called

Options

A. Hypo
B. Pyrogallol
C. Phosphor
D. Autochrome.

Answer

To solve the question about the popular name of trihydroxybenzene, follow these steps:

### Step-by-Step Solution:

1. **Identify the Compound**:
- The question mentions "trihydroxybenzene." This is a chemical compound that has three hydroxyl (–OH) groups attached to a benzene ring.

2. **Understand the Common Names**:
- Trihydroxybenzene is also known as "benzene triol." However, in the context of photography, it has a more commonly used name.

3. **Recall the Uses**:
- Trihydroxybenzene is used as a developer in photography. It acts as a reducing agent and is also utilized in other applications such as hair dye and as a coupling agent in printing.

4. **Determine the Popular Name**:
- The popular name for trihydroxybenzene in photography is "pyrogallol." This is the term that is most recognized in the field.

5. **Evaluate Other Options**:
- The other options provided (Hypo, Phosphor, Autochrome) are not correct for trihydroxybenzene:
- Hypo refers to sodium thiosulfate, used as a fixer in photography.
- Phosphor is a substance that exhibits the phenomenon of luminescence.
- Autochrome is an early color photography process.

6. **Conclusion**:
- Based on the information, the correct answer to the question is "pyrogallol."

### Final Answer:
**Trihydroxybenzene is popularly called Pyrogallol.**

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