Identify corrct set of Atomic numbers belongs to transition elements series

Options

A. 9,21,25,72
B. 21,25,29,57
C. 21,25,30,57
D. 29,48,57,72

Answer

To solve the problem of identifying the correct set of atomic numbers that belong to the transition elements series, we need to understand the periodic table and the characteristics of transition metals.

### Step-by-Step Solution:

1. **Understand Transition Elements**:
Transition elements are found in the d-block of the periodic table. They are characterized by the presence of d electrons in their atomic structure. The transition series includes elements from scandium (Sc, atomic number 21) to zinc (Zn, atomic number 30) in the first transition series.

2. **Identify the Atomic Numbers**:
We need to identify the atomic numbers of the elements in the transition series. The first transition series includes:
- Scandium (Sc) - 21
- Titanium (Ti) - 22
- Vanadium (V) - 23
- Chromium (Cr) - 24
- Manganese (Mn) - 25
- Iron (Fe) - 26
- Cobalt (Co) - 27
- Nickel (Ni) - 28
- Copper (Cu) - 29
- Zinc (Zn) - 30

3. **Check Each Option**:
Now, we will check the given options to see which one contains atomic numbers that fall within the range of 21 to 30, as these are the atomic numbers of the first transition series.

- **Option 1**: 9 (Fluorine) - Not a transition element.
- **Option 2**: 21 (Sc), 25 (Mn), 29 (Cu) - All are transition elements.
- **Option 3**: 30 (Zn) - Zinc is the last transition element in the first series, but it is not considered a transition metal in some contexts due to its full d-orbital configuration.
- **Option 4**: 48 (Cd) - Cadmium is also not considered a transition metal for similar reasons.

4. **Conclusion**:
Based on the analysis, the correct set of atomic numbers that belong to the transition elements series is found in **Option 2**: 21 (Sc), 25 (Mn), and 29 (Cu).

### Final Answer:
The correct set of atomic numbers that belong to the transition elements series is **Option 2**: 21, 25, 29.