M-shell contains sub shell

Options

A. s,p, and d
B. s,p,d and f
C. Only s
D. s and p

Answer

To determine the subshells contained in the M shell, we can follow these steps:

### Step 1: Understand the Shells and Subshells
- The principal quantum number (n) defines the shell, where n=1 corresponds to the K shell, n=2 to the L shell, n=3 to the M shell, and n=4 to the N shell.
- Each shell can contain subshells, which are designated as s, p, d, and f.

### Step 2: Identify the Subshells in the M Shell
- The M shell (n=3) can contain the following subshells:
- 3s
- 3p
- 3d

### Step 3: Determine the Maximum Number of Electrons in Each Subshell
- Each subshell can hold a specific maximum number of electrons:
- The s subshell can hold a maximum of 2 electrons.
- The p subshell can hold a maximum of 6 electrons.
- The d subshell can hold a maximum of 10 electrons.

### Step 4: Calculate the Total Number of Electrons in the M Shell
- To find the total number of electrons that can be accommodated in the M shell, add the maximum electrons from each subshell:
- Total = 2 (from 3s) + 6 (from 3p) + 10 (from 3d) = 18 electrons.

### Step 5: Conclusion
- Therefore, the M shell contains the subshells: s, p, and d.

### Final Answer
The M shell contains the subshells S, P, and D.

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