The nature of bond between `NH_(3) and BF_(3)` is

Options

A. covalent
B. co-ordinate
C. ionic
D. None of these

Answer

To determine the nature of the bond between NH₃ (ammonia) and BF₃ (boron trifluoride), we can follow these steps:

### Step 1: Analyze the Structure of NH₃
- Ammonia (NH₃) has a nitrogen atom bonded to three hydrogen atoms.
- The nitrogen atom has one lone pair of electrons.

### Step 2: Analyze the Structure of BF₃
- Boron trifluoride (BF₃) has a boron atom bonded to three fluorine atoms.
- The boron atom has three valence electrons and forms three covalent bonds with fluorine atoms.
- Boron is electron-deficient, meaning it has only six electrons in its valence shell instead of the full octet (eight electrons).

### Step 3: Identify the Electron Pair Availability
- The lone pair of electrons on the nitrogen atom in NH₃ can be used to bond with the electron-deficient boron atom in BF₃.
- This interaction allows nitrogen to share its lone pair with boron.

### Step 4: Determine the Type of Bond
- The bond formed between NH₃ and BF₃ is a dative bond (also known as a coordinate bond).
- In a dative bond, one atom (in this case, nitrogen) donates both electrons to form a bond with another atom (boron) that has an empty orbital.

### Conclusion
- Therefore, the nature of the bond between NH₃ and BF₃ is a coordinate bond.

### Final Answer
The bond between NH₃ and BF₃ is a **coordinate bond** (Option B).

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