Which of the following statements are part of Bohr's model of hydrogen atom?

Options

A. Energy of the electrons in the orbit is quantized.
B. The electron in the orbit nearest to the nucleus has the lowest energy.
C. Electrons revolve in different orbits around the nucleus.
D. All of these

Explanation

To determine which statements are part of Bohr's model of the hydrogen atom, we need to understand the key postulates of Bohr's theory. Here’s a step-by-step solution:

### Step 1: Understand Bohr's Model
Bohr's model was proposed by Niels Bohr in 1913 to explain the behavior of electrons in hydrogen atoms. It introduced several key concepts regarding electron orbits and energy levels.

### Step 2: Identify Key Postulates
The main postulates of Bohr's model include:
1. Electrons move in fixed orbits around the nucleus, and these orbits correspond to specific energy levels.
2. The energy of the electron is quantized, meaning it can only take on certain discrete values.
3. An electron can move from one orbit to another by absorbing or emitting a specific amount of energy (in the form of a photon).
4. The angular momentum of the electron in these orbits is quantized and is an integer multiple of \( \frac{h}{2\pi} \) (where \( h \) is Planck's constant).

### Step 3: Evaluate the Statements
Now, let’s evaluate the statements provided in the question:
- **Statement 1**: "The Bohr's model of the hydrogen atom is for the mono-electronic species."
- This is true. Bohr's model is specifically applicable to hydrogen and other one-electron systems.

- **Statement 2**: "The energy of the electrons in the orbit is the same."
- This statement is misleading. While electrons in the same orbit have the same energy, the energy levels differ between orbits. So, this statement is partially true but not entirely accurate in the context of Bohr's model.

### Step 4: Conclusion
Based on the evaluation:
- The first statement is a part of Bohr's model.
- The second statement is not accurately representative of Bohr's model as it implies all orbits have the same energy, which is incorrect.

### Final Answer
Only the first statement is part of Bohr's model of the hydrogen atom.

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