Source of `alpha`-particles used in scattering experiment was

Options

A. `._82Bi^216`
B. `._81Bi^216`
C. `._81Bi^214`
D. `._83^214Bi`

Answer

To solve the question regarding the source of alpha particles used in scattering experiments, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Experiment**: The question refers to the scattering experiment, which is commonly known as Rutherford's scattering experiment.

2. **Determine the Source of Alpha Particles**: In Rutherford's scattering experiment, the source of alpha particles was a radioactive material.

3. **Identify the Specific Material**: The specific source of alpha particles used in the experiment was bismuth. Bismuth is denoted by the symbol Bi.

4. **Provide Atomic Information**:
- The atomic number of bismuth (Bi) is 83.
- The atomic mass of bismuth is 214.

5. **Match with Options**:
- Option 1: Bismuth 216 and 82 (Incorrect: Atomic mass and number do not match).
- Option 2: Bismuth 216 and 81 (Incorrect: Both atomic mass and number do not match).
- Option 3: Bismuth 214 and 81 (Incorrect: Atomic mass is correct, but atomic number is wrong).
- Option 4: Bismuth 214 and 83 (Correct: Both atomic mass and number match).

6. **Conclusion**: The correct answer is that the source of alpha particles used in the scattering experiment was bismuth (Bi) with an atomic mass of 214 and an atomic number of 83.

### Final Answer:
The source of alpha particles used in the scattering experiment was **Bismuth (Bi)** with an atomic mass of **214** and an atomic number of **83**.

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