If each orbital can hold a maximum of 3 electrons. Then the number of elements in 2`""^(nd)` period of the periodic table is :

Options

A. 27
B. 9
C. 18
D. 12

Answer

To solve the question of how many elements are in the 2nd period of the periodic table if each orbital can hold a maximum of 3 electrons, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Orbitals in the 2nd Period**:
- The 2nd period consists of elements that have electrons in the 2s and 2p orbitals.
- The principal quantum number (n) for the 2nd period is 2.

2. **Determine the Number of Orbitals**:
- The 2s subshell has **1 orbital**.
- The 2p subshell has **3 orbitals**.
- Therefore, the total number of orbitals in the 2nd period is:
\[ \text{Total Orbitals} = 1 \text{ (from 2s)} + 3 \text{ (from 2p)} = 4 \text{ orbitals} \]

3. **Calculate the Maximum Number of Electrons**:
- If each orbital can hold a maximum of **3 electrons**, then the total number of electrons that can be accommodated in the 4 orbitals is:
\[ \text{Total Electrons} = 4 \text{ (orbitals)} \times 3 \text{ (electrons/orbital)} = 12 \text{ electrons} \]

4. **Conclusion**:
- Since each element corresponds to one electron in the context of filling the orbitals, the maximum number of elements that can be present in the 2nd period is **12**.

### Final Answer:
The number of elements in the 2nd period of the periodic table, if each orbital can hold a maximum of 3 electrons, is **12**.

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