Question

Identify the set of paramagnetic ions among the following:

• A. $V^{2+}, Co^{2+} , Ti^{4+}$
• B. $Ni^{2+}, Cu^{2+} , Zn^{2+}$
• C. $Ti^{3+}, Cu^{2+} , Mn^{3+}$
• D. $Sc^{3+}, Ti^{3+} , V^{3+}$

Answer 1

The Correct Option is C

The ions which contain unpaired electrons exhibit paramagnetic behaviour. 

The electronic configuration of the ions are given below: 

\(Ti ^{3+}=1 s ^{2} 2 s ^{2} 2 p ^{6} 3 s ^{2} 3 p ^{5}\)
\(Cu ^{2+}=1 s ^{2} 2 s ^{2} 2 p ^{6} 3 s ^{2} 3 p ^{5} 3 d ^{9}\)
\(Mn ^{3+}=1 s ^{2} 2 s ^{2} 2 p ^{6} 3 s ^{2} 3 p ^{5} 3 d ^{4}\) 

Thus, all of them have unpaired electrons. Hence, they will show paramagnetic behaviour. 

In option (B) \(V ^{3+}\) does not possess any unpaired electrons. 

In option (C) \(Zn ^{2+}\) does not possess any unpaired electrons. 

Similarly, in option (D) \(Zn ^{2+}\) does not possess any unpaired electrons.

So, the correct option is (C): \(Ti^{3+}, Cu^{2+} , Mn^{3+}\)

Answer 2

Paramagnetism arises from the presence of unpaired electrons in the ion's d-orbitals. Let's analyze the given ions:

- \( \text{Ti}^{3+} \): Titanium in the +3 oxidation state has an electron configuration of \( [Ar] 3d^1 \), meaning it has 1 unpaired electron, making it paramagnetic.
- \( \text{Cu}^{2+} \): Copper in the +2 oxidation state has an electron configuration of \( [Ar] 3d^9 \), meaning it has 1 unpaired electron, making it paramagnetic.
- \( \text{Mn}^{3+} \): Manganese in the +3 oxidation state has an electron configuration of \( [Ar] 3d^4 \), meaning it has 4 unpaired electrons, making it paramagnetic.

Thus, the set of paramagnetic ions is \( \text{Ti}^{3+}, \text{Cu}^{2+}, \text{Mn}^{3+} \).

Hence, the correct answer is (D).