Question

The set with only ambidentate ligands in the following is

• A. \(NO_3^-,\ Br^-,\ C_2O_4^{2-}\)
• B. \(NO_2^-,\ CN^-,\ SCN^-\)
• C. \(NO_2^-,\ C_2O_4^{2-},\ NH_3\)
• D. \(SCN^-,\ CO,\ NH_3\)

Hint:

Common ambidentate ligands are: \[ NO_2^-,\ CN^-,\ SCN^- \] because they can bind through two different atoms.

Answer 1

The Correct Option is B

Step 1: Define ambidentate ligands.
Ambidentate ligands have two different donor atoms and can coordinate through either one, but only one at a time.
Step 2: Check NO2-.
\( NO_2^- \) (nitrite) can coordinate via N (as nitro) or via O (as nitrito). So \( NO_2^- \) IS ambidentate.
Step 3: Check CN-.
\( CN^- \) (cyanide) can coordinate via C (cyanide) or via N (isocyanide). So \( CN^- \) IS ambidentate.
Step 4: Check SCN-.
\( SCN^- \) (thiocyanate) can coordinate via S (thiocyanate) or via N (isothiocyanate). So \( SCN^- \) IS ambidentate.
Step 5: Check ligands in other options.
\( NO_3^- \) coordinates only via O. \( Br^- \) only via Br. \( C_2O_4^{2-} \) is a bidentate chelate ligand (not ambidentate). \( NH_3 \) only via N. \( CO \) only via C.
Step 6: Identify the correct set.
Option 2 contains only \( NO_2^- \), \( CN^- \), and \( SCN^- \), all ambidentate. \[ \boxed{NO_2^-, \ CN^-, \ SCN^-} \]