Electron was discovered by

Options

A. Crookes
B. JJ Thomson
C. Henry
D. Rutherford

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks who discovered the electron.

2. **Recall Historical Context**: The discovery of the electron is a significant milestone in the field of atomic structure and physics.

3. **Identify the Scientist**: The electron was discovered by J. J. Thomson in 1897. He conducted experiments using cathode rays, which led to the identification of the electron as a subatomic particle.

4. **Provide Additional Information**:
- The mass of the electron is approximately \(9.109 \times 10^{-31}\) kg.
- The electric charge of an electron is about \(-1.602 \times 10^{-19}\) coulombs, indicating that it has a negative charge.

5. **Conclusion**: Therefore, the answer to the question "Who discovered the electron?" is J. J. Thomson.

**Final Answer**: The electron was discovered by J. J. Thomson.

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