STATEMENT-1: CO is stronger ligand than `CN^(-)`
STATEMENT-2: `CO` and `CN^(-)` both show synergic bonding with metal .
STATEMENT-3: `CO and N_(2)` are isoelectronic ligands but `N_(2)` is a weaker ligand than CO but stronger than `NH_(3)` .

Options

A. TFT
B. TTF
C. FFT
D. FTT

Answer

To analyze the statements regarding the ligands CO and CN⁻, we will evaluate each statement step by step.

### Step 1: Evaluate Statement 1
**Statement 1:** CO is stronger ligand than CN⁻.

- In the spectrochemical series, ligands are arranged based on their field strength. CO (carbon monoxide) is indeed a stronger ligand than CN⁻ (cyanide ion). This is because CO has a greater ability to donate electron density to the metal center due to its ability to engage in π-backbonding. Therefore, this statement is **true**.

### Step 2: Evaluate Statement 2
**Statement 2:** CO and CN⁻ both show synergic bonding with metal.

- Synergic bonding refers to the simultaneous donation of electron density from the ligand to the metal and the back-donation of electron density from the metal to the ligand. Both CO and CN⁻ can engage in this type of bonding. CO donates its lone pair to the metal and can accept back-donated electrons from the filled d-orbitals of the metal into its empty π* orbitals. Similarly, CN⁻ also exhibits this behavior. Hence, this statement is **true**.

### Step 3: Evaluate Statement 3
**Statement 3:** CO and N₂ are isoelectronic ligands but N₂ is a weaker ligand than CO but stronger than NH₃.

- Isoelectronic ligands are those that have the same number of electrons. CO has 14 electrons (6 from carbon and 8 from oxygen), and N₂ also has 14 electrons (7 from each nitrogen). Thus, they are isoelectronic. However, the claim that N₂ is a weaker ligand than CO but stronger than NH₃ is incorrect. In the spectrochemical series, NH₃ is actually a stronger ligand than N₂. Therefore, this statement is **false**.

### Conclusion
- **Statement 1:** True
- **Statement 2:** True
- **Statement 3:** False

The final answer is that the statements are true, true, and false respectively.