How many electrons, protons and photons are involved in the lysis of water to evolve one molecule of oxygen ?

Options

A. ` 4e^(-), 4H^(+)` and 4 photons
B. ` 4e^(-), 4H^(+)` and 8 photons
C. ` 2e^(-) , 2H^(+)` and 8 photons
D. `2e^(-) and 2H^(+)` and 4 photons

Answer

To determine how many electrons, protons, and photons are involved in the lysis of water to evolve one molecule of oxygen, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Water Lysis**: The lysis of water refers to the splitting of water molecules (H₂O) during the process of photosynthesis, which occurs in the thylakoid membranes of chloroplasts. This process is crucial for oxygen evolution.

2. **Chemical Equation for Water Lysis**: The balanced chemical equation for the lysis of water is:
\[ 2H_2O \rightarrow 4H^+ + 4e^- + O_2 \]
This equation indicates that two molecules of water yield four hydrogen ions (H⁺), four electrons (e⁻), and one molecule of oxygen (O₂).

3. **Calculating for One Molecule of Oxygen**: Since the equation shows that two molecules of water produce one molecule of oxygen, we need to analyze how many electrons and protons are produced in this process:
- **Electrons**: From the equation, for every two water molecules, four electrons are produced. Therefore, for one molecule of oxygen, four electrons are involved.
- **Protons**: Similarly, for every two water molecules, four protons are produced. Thus, for one molecule of oxygen, four protons are also involved.

4. **Photons Involvement**: The process of water lysis is driven by light energy, which is captured by chlorophyll in the thylakoid membranes. For every molecule of oxygen produced, an equal number of photons are absorbed to facilitate the reaction. Therefore, four photons are also involved in the process.

5. **Final Count**:
- Electrons: 4
- Protons: 4
- Photons: 4

### Summary:
To evolve one molecule of oxygen from the lysis of water, **4 electrons, 4 protons, and 4 photons** are involved.