If the atomic number of an element is 36, the number of electrons present in the M-shell is

Options

A. 18
B. 19
C. 10
D. 14

Answer

To determine the number of electrons present in the M-shell for an element with an atomic number of 36, we can follow these steps:

### Step 1: Identify the Element
The atomic number of 36 corresponds to the element Krypton (Kr).

### Step 2: Write the Electronic Configuration
The electronic configuration of Krypton can be written as:
\[ \text{Krypton (Kr): } 1s^2 \, 2s^2 \, 2p^6 \, 3s^2 \, 3p^6 \, 4s^2 \, 3d^{10} \, 4p^6 \]

### Step 3: Determine the Shells and Their Electrons
- **K Shell (n=1)**: Can hold a maximum of 2 electrons.
- Contains: 2 electrons (1s²)

- **L Shell (n=2)**: Can hold a maximum of 8 electrons.
- Contains: 8 electrons (2s² 2p⁶)

- **M Shell (n=3)**: Can hold a maximum of 18 electrons.
- Contains: 8 electrons (3s² 3p⁶) + 10 electrons (3d¹⁰) = 18 electrons

### Step 4: Conclusion
The number of electrons present in the M-shell of Krypton is **18**.

### Final Answer
The number of electrons present in the M-shell for the element with atomic number 36 (Krypton) is **18**.

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