As applied to periodic table, which of the following sets include only magic number?

Options

A. 2,8,8,18,19,32
B. 2,8,18,32
C. 8,8,18,18
D. 2,18,18,32

Answer

To determine which set includes only magic numbers as applied to the periodic table, we need to first understand what magic numbers are and then analyze the given options.

### Step-by-Step Solution:

1. **Understanding Magic Numbers**:
- Magic numbers in the context of the periodic table refer to the number of electrons that can completely fill the electron shells in an atom. These numbers are significant because they indicate stable configurations.
- The known magic numbers are: **2, 8, 18, 32**.

2. **Identifying the Options**:
- We need to evaluate the given sets to see which one contains only the magic numbers without any repetitions or additional numbers.

3. **Evaluating Each Set**:
- **Set 1**: 2, 8, 19
- This set contains **19**, which is not a magic number. Thus, this set is **not valid**.
- **Set 2**: 2, 8, 18, 32
- This set includes **2, 8, 18, and 32**, all of which are magic numbers. Thus, this set is **valid**.
- **Set 3**: 8, 8, 18, 18
- This set has repetitions of **8** and **18** and is missing **2** and **32**. Thus, this set is **not valid**.
- **Set 4**: 2, 18, 18, 32
- This set has a repetition of **18** and is missing **8**. Thus, this set is **not valid**.

4. **Conclusion**:
- The only set that includes only magic numbers without any repetitions or omissions is **Set 2: 2, 8, 18, 32**.

### Final Answer:
The correct set that includes only magic numbers is **Set 2: 2, 8, 18, 32**.