Total no. of vacant orbitals in valence shell of sulphur when it undergoes formation of `SF_(4)` :-

Options

A. 5
B. 4
C. 3
D. 2

Answer

To determine the total number of vacant orbitals in the valence shell of sulfur when it forms SF₄, we can follow these steps:

### Step 1: Determine the electronic configuration of sulfur
Sulfur (S) has an atomic number of 16. Its electronic configuration is:
- 1s² 2s² 2p⁶ 3s² 3p⁴

### Step 2: Identify the valence shell
The valence shell for sulfur is the third shell (n=3), which includes the 3s and 3p orbitals. The configuration in the valence shell is:
- 3s² 3p⁴

### Step 3: Count the electrons in the valence shell
In the valence shell:
- 3s has 2 electrons
- 3p has 4 electrons

Total electrons in the valence shell = 2 (from 3s) + 4 (from 3p) = 6 electrons.

### Step 4: Determine the hybridization in SF₄
When sulfur forms SF₄, it undergoes sp³ hybridization. In sp³ hybridization, one s orbital and three p orbitals mix to form four equivalent sp³ hybrid orbitals.

### Step 5: Identify the orbitals involved in hybridization
In the case of sp³ hybridization:
- The 3s orbital is used, and three of the 3p orbitals are also used.
- This leaves one 3p orbital and the 3d orbitals available for bonding.

### Step 6: Count the vacant orbitals
In the third shell, the 3d subshell can hold a maximum of 5 orbitals. Since sulfur does not have any electrons in the 3d subshell in its ground state, all 5 of these orbitals are vacant.

### Conclusion
Thus, the total number of vacant orbitals in the valence shell of sulfur when it forms SF₄ is 5 (from the 3d subshell).

### Final Answer
The total number of vacant orbitals in the valence shell of sulfur when it undergoes formation of SF₄ is **5**.

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