Dative bond is present in :-

Options

A. `KI_(3)`
B. `KNO_(2)`
C. `KHF_(2)`
D. All

Answer

To determine where a dative bond is present among the given options, let's analyze each compound step by step.

### Step 1: Understand the concept of a dative bond
A dative bond (or coordinate bond) occurs when one atom donates both electrons to form a covalent bond. This typically happens when one atom has a lone pair of electrons and another atom has an empty orbital.

### Step 2: Analyze K-I3 (Potassium Iodide)
- In K-I3, the iodine atoms form a triiodide ion (I3^-).
- The central iodine atom has a negative charge and can donate one of its lone pair electrons to bond with another iodine atom.
- This results in the formation of a dative bond because one iodine atom donates both electrons to bond with another iodine atom.
- Therefore, K-I3 contains a dative bond.

### Step 3: Analyze K-NO2 (Potassium Nitrite)
- In K-NO2, the nitrite ion (NO2^-) is present.
- The nitrogen atom in NO2 has a total of 5 valence electrons and forms bonds with two oxygen atoms.
- The bonding involves sharing of electrons, and there are no lone pairs that are completely donated to form a bond.
- Thus, K-NO2 does not contain a dative bond.

### Step 4: Analyze K-HF2 (Potassium Difluoride)
- In K-HF2, potassium donates its electron to fluorine, forming an ionic bond.
- The bonding between hydrogen and fluorine is covalent, as they share electrons.
- There is no complete donation of a lone pair from one atom to another in this case.
- Therefore, K-HF2 does not contain a dative bond.

### Conclusion
The only compound among the options that contains a dative bond is K-I3.

### Final Answer
Dative bond is present in K-I3.

---