Which of the following statement concerning Bohr's model is //are true ?

Options

A. It predicts that probability of electron near nucless is more
B. Angular momentum of electron in H `= nh//2pi`
C. It int introduces the idea of stationary states
D. It explains line spectrum of hydrogen

Answer

To determine which statements concerning Bohr's model are true, we will analyze each statement based on the principles of Bohr's atomic theory.

### Step-by-Step Solution:

1. **Statement Analysis**:
- **Statement 1**: "It predicts that the probability of an electron near the nucleus is more."
- **Analysis**: This statement is incorrect. According to Bohr's model, electrons revolve in specific circular orbits around the nucleus, and the probability of finding an electron is not necessarily higher near the nucleus. Instead, it is determined by the allowed energy levels.

2. **Statement 2**: "Angular momentum of electron is \( L = n \frac{h}{2\pi} \)."
- **Analysis**: This statement is correct. Bohr's model states that the angular momentum of an electron in a permitted orbit is quantized and given by the formula \( L = n \frac{h}{2\pi} \), where \( n \) is a positive integer (quantum number) and \( h \) is Planck's constant.

3. **Statement 3**: "It introduces the idea of stationary state."
- **Analysis**: This statement is also correct. Bohr introduced the concept of stationary states, where electrons occupy specific orbits without radiating energy, thus remaining stable.

4. **Statement 4**: "It explains the line spectrum of hydrogen."
- **Analysis**: This statement is correct. Bohr's model successfully explains the line spectrum of hydrogen by quantizing the energy levels of the electron, leading to the emission or absorption of light at specific wavelengths.

5. **Conclusion**:
- Based on the analysis, the true statements concerning Bohr's model are:
- Statement 2: Correct
- Statement 3: Correct
- Statement 4: Correct
- Therefore, the correct answers are statements 2, 3, and 4.

### Summary of True Statements:
- The second, third, and fourth statements regarding Bohr's model are true.