Hill used dye for his famous Hill reaction

Options

A. Sulphur green
B. Eosine
C. Methylene blue
D. Dichlorophenol indophenol.

Answer

**Step-by-Step Solution:**

1. **Understanding the Hill Reaction**: The Hill reaction is a part of photosynthesis that involves the light-dependent reactions. It was studied by Robert Hill, who demonstrated that oxygen produced during photosynthesis comes from the photolysis (splitting) of water.

2. **Identifying the Role of Dyes**: In his experiments, Hill used a dye to measure the rate of photosynthesis. This dye acts as an electron acceptor in the light-dependent reactions.

3. **Analyzing the Options**: The question provides four options for the dye used in the Hill reaction:
- a) Sulphur green
- b) Eosin
- c) Methylene blue
- d) Dichlorophenol Indophenol (DCPIP)

4. **Recalling the Correct Dye**: The correct dye used by Hill is DCPIP (Dichlorophenol Indophenol). In its reduced state, DCPIP is colorless, and when it is oxidized, it turns blue. This color change is used to indicate the progress of the reaction.

5. **Conclusion**: Based on the information gathered, the correct answer to the question is option d) Dichlorophenol Indophenol.

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