The two electrons in K sub-shell will differ in

Options

A. Principal quantum number
B. Azimuthal quantum number
C. Magnetic quantum number
D. Spin quantum number

Explanation

To determine how the two electrons in the K subshell differ, we need to analyze their quantum numbers. Here’s a step-by-step solution:

### Step 1: Understand Quantum Numbers
Quantum numbers are a set of four numbers that describe the position and energy of electrons in an atom. The four types of quantum numbers are:
1. **Principal Quantum Number (n)**: Indicates the energy level or shell.
2. **Azimuthal Quantum Number (l)**: Indicates the subshell (s, p, d, f).
3. **Magnetic Quantum Number (m)**: Indicates the orientation of the orbital.
4. **Spin Quantum Number (ms)**: Indicates the spin direction of the electron.

### Step 2: Identify Quantum Numbers for K Subshell
The K subshell corresponds to:
- **n = 1** (first energy level)
- **l = 0** (s subshell, since l = 0 corresponds to s)
- **m = 0** (only one orientation for s subshell)

### Step 3: Determine the Spin Quantum Number
The two electrons in the K subshell will occupy the same orbital (since there is only one orbital in the 1s subshell). However, they must have opposite spins due to the Pauli Exclusion Principle, which states that no two electrons can have the same set of quantum numbers.

- For the first electron:
- **ms = +1/2** (spin up)

- For the second electron:
- **ms = -1/2** (spin down)

### Step 4: Conclusion
Thus, the two electrons in the K subshell differ in their spin quantum number. They have the same values for the principal quantum number (n), azimuthal quantum number (l), and magnetic quantum number (m), but differ in their spin quantum number (ms).

### Final Answer
The two electrons in the K subshell will differ in their **spin quantum number**.

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