The electron in Bohr's model of hydrogen atom is pictured as revolving around the nucleus in order for it to

Options

A. emit protons
B. keep from being pulled into the nucleus
C. keep from being repelled by the nucleus
D. possess energy.

Explanation

To solve the question regarding the electron in Bohr's model of the hydrogen atom, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Bohr's Model**:
- Bohr's model describes the hydrogen atom as having an electron that revolves around a nucleus in fixed orbits. These orbits are quantized, meaning the electron can only occupy certain energy levels.

2. **Energy Levels**:
- The energy of the electron in a particular orbit is given by the formula:
\[ E = -\frac{13.6 \, \text{eV} \cdot z^2}{n^2} \]
where \( z \) is the atomic number (which is 1 for hydrogen) and \( n \) is the principal quantum number (the orbit number).

3. **Purpose of Electron Revolving**:
- The question asks why the electron is pictured as revolving around the nucleus. The key reason is to maintain a certain energy state. If the electron were to fall into the nucleus, it would lose energy and collapse into it.

4. **Analyzing the Options**:
- **Emit protons**: Incorrect, as electrons do not emit protons.
- **Keep from being pulled into the nucleus**: While this is a consideration, it does not directly address the energy aspect.
- **Keep from being repelled by the nucleus**: Incorrect, as electrons are negatively charged and are attracted to the positively charged nucleus.
- **Possess energy**: Correct, as the electron revolves in fixed orbits to maintain a specific energy level.

5. **Conclusion**:
- Therefore, the correct answer is that the electron in Bohr's model of the hydrogen atom is pictured as revolving around the nucleus in order for it to **possess energy**.

### Final Answer:
The electron in Bohr's model of the hydrogen atom is pictured as revolving around the nucleus in order for it to **possess energy**.

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