Which of the following complexes exhibits the highest paramagnetic behaviour?
where gly=glycine, en=ethylenediamine and bipy =bipyridyl
(At. no. `Ti=22, V=23, Fe=26, Co=27`)

Options

A. (a) `[Fe(en)(bipy)(NH_3)_2]^(2+)`
B. (b) `[Co(OX)_2(OH)_2]^(-)`
C. (c) `[Ti(NH_3)_6]^(3+)`
D. (d) `[V(gly)_2(OH)_2(NH_3)_2]^(+)`

Explanation

To determine which of the given complexes exhibits the highest paramagnetic behavior, we need to analyze each complex based on the oxidation state of the metal ion, the electron configuration, and the nature of the ligands involved.

### Step-by-Step Solution:

1. **Identify the Metal and its Oxidation State**:
- For each complex, identify the metal ion and determine its oxidation state based on the ligands present.
- **Complex 1**: [Ti(en)2(bipy)] → Titanium (Ti) is in +2 oxidation state.
- **Complex 2**: [Co(C2O4)2] → Cobalt (Co) is in +5 oxidation state.
- **Complex 3**: [Ti(NH3)6] → Titanium (Ti) is in +3 oxidation state.
- **Complex 4**: [V(gly)3] → Vanadium (V) is in +3 oxidation state.

2. **Determine the Electron Configuration**:
- Use the atomic numbers to find the electron configurations of the metal ions in their respective oxidation states.
- **Ti (22)**: Ti^2+ → Argon (Ar) 3d^2
- **Co (27)**: Co^5+ → Argon (Ar) 3d^7 (removing 5 electrons from 4s and 3d)
- **Ti (22)**: Ti^3+ → Argon (Ar) 3d^1
- **V (23)**: V^3+ → Argon (Ar) 3d^2

3. **Consider the Ligands**:
- Determine whether the ligands are strong field or weak field ligands.
- **en (ethylenediamine)** and **bipy (bipyridyl)** are strong field ligands.
- **C2O4 (oxalate)** is also a strong field ligand.
- **NH3 (ammonia)** is a weak field ligand.
- **gly (glycine)** is a weak field ligand.

4. **Electron Pairing**:
- Strong field ligands cause pairing of electrons, while weak field ligands do not.
- For **Ti^2+** (3d^2) with strong field ligands: 2 paired electrons → 0 unpaired electrons.
- For **Co^5+** (3d^7) with strong field ligands: 6 paired electrons, 1 unpaired electron → 1 unpaired electron.
- For **Ti^3+** (3d^1) with weak field ligands: 1 unpaired electron → 1 unpaired electron.
- For **V^3+** (3d^2) with weak field ligands: 2 unpaired electrons → 2 unpaired electrons.

5. **Compare Paramagnetic Behavior**:
- The more unpaired electrons, the higher the paramagnetic behavior.
- **Complex 1**: 0 unpaired electrons (Ti^2+).
- **Complex 2**: 1 unpaired electron (Co^5+).
- **Complex 3**: 1 unpaired electron (Ti^3+).
- **Complex 4**: 2 unpaired electrons (V^3+).

6. **Conclusion**:
- The complex with the highest paramagnetic behavior is **[V(gly)3]**, as it has the highest number of unpaired electrons (2 unpaired electrons).

### Final Answer:
The complex that exhibits the highest paramagnetic behavior is **[V(gly)3]**.