Which of the following reactions is given by van Niel

Options

A. `2H_(2)O+CO_(2) overset("light")(rarr) CH_(2)O+H_(2)O +O_(2)`
B. `CO_(2)+H_(2)O overset("light")(rarr) CH_(2)O+O_(2)`
C. `6O_(2)+12 H_(2)O overset("light")(rarr) C_(6)H_(12)O_(6)+6H_(2)O`+6CO_(2)`
D. `2 H_(2)O+CO_(2) overset("light")(rarr) CH_(2)O+H_(2)O`.

Answer

To answer the question "Which of the following reactions is given by van Niel?", we need to understand the contributions of van Niel to the field of photosynthesis.

### Step-by-Step Solution:

1. **Understand van Niel's Contribution**: Van Niel was a Dutch-American microbiologist who studied photosynthetic bacteria, particularly purple and green sulfur bacteria. In 1931, he proposed that photosynthesis is a light-dependent redox reaction.

2. **Identify the Key Components**: Van Niel's work highlighted that during photosynthesis, water (H2O) serves as the hydrogen donor. He concluded that in the process of photosynthesis, carbon dioxide (CO2) is reduced to form carbohydrates, while water is oxidized to release oxygen (O2).

3. **Formulate the Reaction**: Based on van Niel's findings, the general reaction for photosynthesis can be represented as:
\[ 2H_2O + CO_2 \xrightarrow{\text{light}} (CH_2O) + O_2 \]
Here, carbohydrates (represented as (CH2O)) are produced, and oxygen is released as a byproduct.

4. **Evaluate the Given Options**: We need to look at the provided options and identify which one aligns with van Niel's proposed reaction. The correct reaction should indicate that water is the hydrogen donor, and oxygen is released during the process.

5. **Select the Correct Option**: After evaluating the options, we find that the correct reaction that reflects van Niel's findings is:
\[ \text{Water + Carbon Dioxide} \xrightarrow{\text{light}} \text{Sugar + Oxygen} \]
This matches the understanding that water is oxidized, and oxygen is released.

### Conclusion:
The correct reaction given by van Niel is the one that indicates water and carbon dioxide react in the presence of light to produce sugar and release oxygen.

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