Which quantum number is sufficient to describe the electron in hydrogen atom?

Options

A. l
B. n
C. m
D. s

Answer

To determine which quantum number is sufficient to describe the electron in a hydrogen atom, we can follow these steps:

### Step 1: Understand the Quantum Numbers
Quantum numbers are used to describe the properties of electrons in an atom. There are four types of quantum numbers:
1. **Principal Quantum Number (n)**: Indicates the energy level and distance from the nucleus.
2. **Azimuthal Quantum Number (l)**: Indicates the shape of the orbital.
3. **Magnetic Quantum Number (m)**: Indicates the orientation of the orbital.
4. **Spin Quantum Number (s)**: Indicates the spin of the electron.

### Step 2: Analyze the Hydrogen Atom
The hydrogen atom has only one electron. The electron's state can be described using quantum numbers. Since there is only one electron, the complexity of multiple electrons (which would require more quantum numbers) does not apply here.

### Step 3: Identify the Relevant Quantum Number
For the hydrogen atom:
- The **Principal Quantum Number (n)** is sufficient to describe the electron's energy level, distance from the nucleus, and the shell it occupies.
- The other quantum numbers (l, m, and s) provide additional details that are not necessary for a single electron in hydrogen.

### Step 4: Conclusion
Thus, the Principal Quantum Number (n) is sufficient to describe the electron in a hydrogen atom. It tells us the energy level and the distance of the electron from the nucleus.

### Final Answer
The quantum number sufficient to describe the electron in a hydrogen atom is the **Principal Quantum Number (n)**.

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