Question

Number of ambidentate ligands among the following is ____.
\[ \text{NO}_2^{-}, \text{SCN}^{-}, \text{C}_2\text{O}_4^{2-}, \text{NH}_3, \text{CN}^{-}, \text{SO}_4^{2-}, \text{H}_2\text{O} \]

Answer 1

Correct Answer: 3

To determine the number of ambidentate ligands among the given species, we first need to understand what constitutes an ambidentate ligand. An ambidentate ligand can coordinate to a metal ion through two different atoms. We will analyze each ligand:

1. \(\text{NO}_2^{-}\): This ligand can bind through either the nitrogen or oxygen atom. Hence, it is an ambidentate ligand.
2. \(\text{SCN}^{-}\): This ligand can coordinate through either the sulfur or nitrogen atom, making it ambidentate.
3. \(\text{C}_2\text{O}_4^{2-}\): Although this is a bidentate ligand, it coordinates through both oxygens of the same types and is not ambidentate.
4. \(\text{NH}_3\): Ammonia only coordinates through the nitrogen atom, so it is not ambidentate.
5. \(\text{CN}^{-}\): This ligand can bind through either the carbon or nitrogen atom, classifying it as ambidentate.
6. \(\text{SO}_4^{2-}\): Sulfate is a bidentate ligand capable of binding through two oxygen atoms; however, it is not ambidentate.
7. \(\text{H}_2\text{O}\): Water binds only through the oxygen, making it non-ambidentate.

Thus, the ambidentate ligands among the listed are \(\text{NO}_2^{-}\), \(\text{SCN}^{-}\), and \(\text{CN}^{-}\). This gives us a total of 3 ambidentate ligands, which is within the specified range (3,3).

Answer 2

Step 1: Define ambidentate ligands
Ambidentate ligands are ligands that can coordinate to a metal center through two different atoms.

Step 2: Analyze the ligands

1. \(\text{NO}_2^-\): Ambidentate ligand; can bind through N or O.
2. \(\text{SCN}^-\): Ambidentate ligand; can bind through S or N.
3. \(\text{C}_2\text{O}_4^{2-}\): Not ambidentate; it is a bidentate ligand.
4. \(\text{NH}_3\): Not ambidentate; monodentate ligand binding through N.
5. \(\text{CN}^-\): Ambidentate ligand; can bind through C or N.
6. \(\text{SO}_4^{2-}\): Not ambidentate; it is a bidentate ligand.
7. \(\text{H}_2\text{O}\): Not ambidentate; monodentate ligand binding through O.

Step 3: Count ambidentate ligands
Ambidentate ligands are:
\[ \text{NO}_2^-, \, \text{SCN}^-, \, \text{CN}^-. \] Total number = 3.

Thus, the correct answer: 3.