The total number of vacant orbitals involved in bond formation in diborane is

Options

A. 2
B. 3
C. 4
D. 6

Answer

To determine the total number of vacant orbitals involved in bond formation in diborane (B2H6), we can follow these steps:

### Step 1: Understand the Structure of Diborane
Diborane consists of two boron atoms and six hydrogen atoms. The boron atoms are bonded to each other and to the hydrogen atoms in a unique arrangement.

**Hint:** Visualize the structure of diborane to understand how the atoms are arranged.

### Step 2: Determine the Electronic Configuration of Boron
Boron has an atomic number of 5, which means its electronic configuration is:
- Ground state: 1s² 2s² 2p¹
- Excited state: 1s² 2s¹ 2p² (where one electron from 2s is promoted to 2p)

**Hint:** Remember that the excited state configuration is important for hybridization.

### Step 3: Identify the Hybridization of Boron
In diborane, boron undergoes hybridization to form sp³ hybrid orbitals. This involves the mixing of one 2s orbital and three 2p orbitals (2p_x, 2p_y, and 2p_z).

**Hint:** Consider how the orbitals mix to form new hybrid orbitals.

### Step 4: Count the Vacant Orbitals
In the case of diborane:
- Each boron atom contributes one vacant 2p_z orbital after hybridization.
- Since there are two boron atoms, the total number of vacant orbitals is 2 (one from each boron atom).

**Hint:** Keep track of how many boron atoms are present and how many vacant orbitals each contributes.

### Step 5: Conclusion
The total number of vacant orbitals involved in bond formation in diborane is 2.

**Final Answer:** The total number of vacant orbitals in diborane is **2**.

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