Assertion :- `CH_4` obeys the octet rule.
Reason :- During the formation of `CH_4` molecules, carbon atom achieves an octet.

Options

A. If both Assertion and Reason are CORRECT and Reason is the CORRECT explanation of the Assertion
B. If both Assertion and Reason are CORRECT but Reason is not the CORRECT explanation of the Assertion.
C. If Assertion is CORRECT but Reason is INCORRECT.
D. If Assertion is INCORRECT but Reason is CORRECT.

Answer

To analyze the given assertion and reason, let's break down the statements step by step.

### Step 1: Understand the Assertion
The assertion states that CH₄ (methane) obeys the octet rule. The octet rule suggests that atoms are most stable when they have eight electrons in their valence shell.

**Hint:** Recall what the octet rule states and how it applies to atoms in molecules.

### Step 2: Understand the Reason
The reason provided states that during the formation of CH₄, the carbon atom achieves an octet. To verify this, we need to look at the electron configuration of carbon and hydrogen.

**Hint:** Consider the number of valence electrons for carbon and hydrogen.

### Step 3: Analyze Carbon's Valence Electrons
Carbon has 4 valence electrons (2s² 2p²), while hydrogen has 1 valence electron (1s¹). In CH₄, carbon will form four bonds with four hydrogen atoms.

**Hint:** Count the total number of electrons involved in bonding.

### Step 4: Formation of CH₄
In the formation of CH₄, carbon shares its four valence electrons with four hydrogen atoms. Each hydrogen atom contributes one electron, resulting in four shared pairs of electrons.

**Hint:** Visualize the sharing of electrons between carbon and hydrogen.

### Step 5: Achieving the Octet
By sharing electrons with four hydrogen atoms, carbon effectively has access to a total of 8 electrons in its valence shell (4 from its own and 4 from hydrogen). Thus, carbon achieves an octet.

**Hint:** Think about how sharing electrons allows carbon to attain a stable electron configuration.

### Step 6: Conclusion
Both the assertion and reason are correct. CH₄ does obey the octet rule, and the reason explains how carbon achieves an octet during the formation of the molecule.

**Final Answer:** Both the assertion and reason are correct, and the reason is the correct explanation of the assertion.