Who was the first to explain the evolution of oxygen during photosynthesis

Options

A. Dutrochet
B. Joseph Priestley
C. V.Helmont
D. Wilstatter

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the scientist who first explained the evolution of oxygen during photosynthesis.

2. **Identifying Key Terms**: The key term here is "evolution of oxygen," which refers to the process by which oxygen is produced as a byproduct of photosynthesis.

3. **Reviewing the Options**: The options provided are Dutrochet, Joseph Priestley, V. Helmholtz, and Will Slater. We need to determine which of these scientists is associated with the discovery of oxygen evolution in photosynthesis.

4. **Historical Context**: Joseph Priestley conducted experiments in the 18th century that contributed significantly to our understanding of gases and their role in respiration and photosynthesis.

5. **Priestley's Experiment**: In his experiments, Priestley placed a burning candle and a mouse in a sealed jar. He observed that the candle extinguished and the mouse died due to the depletion of oxygen. He then introduced a plant into the jar, which produced oxygen, allowing the mouse to survive and the candle to burn again.

6. **Conclusion**: Based on the experiments conducted by Joseph Priestley, he was the first to explain the evolution of oxygen during photosynthesis. Therefore, the correct answer is **Joseph Priestley**.

7. **Final Answer**: The first to explain the evolution of oxygen during photosynthesis was **Joseph Priestley**.

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