Octer rule is not violated in case of

Options

A. methane
B. boron trifluoride
C. sulphur hexafluoride
D. aluminnium chloride

Explanation

To determine in which case the octet rule is not violated, we need to analyze the octet rule itself and apply it to different molecules. Here’s the step-by-step solution:

### Step 1: Understand the Octet Rule
The octet rule states that atoms tend to form bonds in such a way that they have eight electrons in their valence shell, which makes them stable. This rule is primarily applicable to main group elements.

**Hint:** Remember that the octet rule is about achieving a stable electron configuration of eight valence electrons.

### Step 2: Analyze Methane (CH₄)
- **Carbon** has 4 valence electrons and needs 4 more to complete its octet.
- In methane, carbon forms 4 single bonds with 4 hydrogen atoms.
- Each hydrogen contributes 1 electron, giving carbon a total of 8 electrons in its valence shell.

**Hint:** Check how many electrons each atom contributes to the central atom to see if the octet is achieved.

### Step 3: Analyze Boron Trifluoride (BF₃)
- **Boron** has 3 valence electrons and forms 3 bonds with fluorine.
- Boron only has 6 electrons in its valence shell after bonding, which means it does not satisfy the octet rule.

**Hint:** Look for atoms that do not have 8 electrons after bonding.

### Step 4: Analyze Sulfur Hexafluoride (SF₆)
- **Sulfur** has 6 valence electrons and forms 6 bonds with fluorine.
- After bonding, sulfur has 12 electrons in its valence shell, which means it exceeds the octet rule.

**Hint:** Identify cases where the total number of electrons exceeds 8.

### Step 5: Analyze Aluminum Chloride (AlCl₃)
- **Aluminum** has 3 valence electrons and forms 3 bonds with chlorine.
- After bonding, aluminum has only 6 electrons in its valence shell, which means it does not satisfy the octet rule.

**Hint:** Again, check if the central atom has less than 8 electrons after forming bonds.

### Conclusion
From the analysis, we find that the only molecule where the octet rule is not violated is **Methane (CH₄)**. In this case, carbon achieves a full octet by sharing electrons with hydrogen atoms.

**Final Answer:** The octet rule is not violated in the case of Methane (CH₄).