Assertion : In the formation of water molecule, both hydrogen and oxygen atoms attain octet of electrons.
Reason : Oxygen atom forms two ionic or electrovalent bonds with two hydrogen atoms.

Options

A. both assertion and reason are true and reason is the correct explanation of assertion.
B. both assertion and reason are true but reason in not the correct explanation of assertion.
C. assertion is true but reason is false.
D. both assertion and reason are false.

Explanation

To solve the assertion-reason question, let's analyze both the assertion and the reason step by step.

### Step 1: Analyze the Assertion
The assertion states: "In the formation of a water molecule, both hydrogen and oxygen atoms attain octet of electrons."

- **Understanding the Assertion**:
- A water molecule (H₂O) consists of two hydrogen atoms and one oxygen atom.
- Hydrogen has one electron (1s¹) and needs one more electron to achieve a stable configuration, which is called a duplet (not an octet).
- Oxygen has six valence electrons (1s² 2s² 2p⁴) and needs two more electrons to complete its octet.

**Conclusion for Step 1**: The assertion is false because hydrogen does not attain an octet; it attains a duplet.

### Step 2: Analyze the Reason
The reason states: "Oxygen atom forms two ionic or electrovalent bonds with two hydrogen atoms."

- **Understanding the Reason**:
- In the formation of water, oxygen does not form ionic bonds with hydrogen. Instead, it shares electrons with hydrogen atoms to form covalent bonds.
- Ionic bonds involve the transfer of electrons, while covalent bonds involve the sharing of electrons.

**Conclusion for Step 2**: The reason is also false because the bonds in water are covalent, not ionic.

### Final Conclusion
Both the assertion and the reason are false.

### Answer
The correct option is that both the assertion and reason are false.

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