Transition metals are often paramagnetic owing to the presence of

Options

A. valency electrons in the outer two electrons shells
B. unpaired electrons in their atoms
C. vacant d orbitals in the n th orbit
D. electrons in d orbitals of the (n-1) orbit.

Explanation

To solve the question "Transition metals are often paramagnetic owing to the presence of," we need to analyze the properties of transition metals, particularly focusing on their electron configurations and the concept of paramagnetism.

### Step-by-Step Solution:

1. **Understanding Paramagnetism**:
- Paramagnetism occurs in substances that have unpaired electrons. These unpaired electrons create a magnetic moment, allowing the substance to be attracted to a magnetic field.

2. **Identifying Transition Metals**:
- Transition metals are elements found in the d-block of the periodic table. They include elements like Scandium (Sc), Titanium (Ti), Vanadium (V), Chromium (Cr), and others.

3. **Electron Configuration of Transition Metals**:
- Transition metals have partially filled d-orbitals. For example:
- Scandium (Sc): [Ar] 3d¹ 4s²
- Titanium (Ti): [Ar] 3d² 4s²
- Vanadium (V): [Ar] 3d³ 4s²
- Chromium (Cr): [Ar] 3d⁵ 4s¹ (notable for its half-filled d-orbital)

4. **Presence of Unpaired Electrons**:
- In these configurations, we can see that some electrons in the d-orbitals are unpaired. For instance, in Chromium, there are 5 unpaired electrons in the d-orbital.

5. **Conclusion**:
- Since transition metals often have unpaired electrons in their d-orbitals, they are typically paramagnetic. Therefore, the correct answer to the question is that transition metals are often paramagnetic owing to the presence of unpaired electrons in their atoms.

### Final Answer:
Transition metals are often paramagnetic owing to the presence of **unpaired electrons in their atoms**.