Statement-1. Ammonia has lower molecular mass than `N_(2)`.
Statement-2. At a given temperature te rate of diffusion is inversely proportional to the square root of its density.

Options

A. Statement-1 is true, statement-2 is also true, statement-2 is correct explanation of statement-1
B. Statement-1 is true, statement-2 is also true, statement-2 is not correct explanation of statement-1
C. Statement-1 is true, statement-2 is true.
D. Statement-1 is false, statement-2 is true.

Explanation

To solve the question, we need to analyze both statements provided:

**Step 1: Evaluate Statement-1**
- Statement-1 claims that ammonia (NH₃) has a lower molecular mass than nitrogen gas (N₂).
- The molar mass of ammonia (NH₃) can be calculated as follows:
- Nitrogen (N) has a molar mass of approximately 14 g/mol.
- Hydrogen (H) has a molar mass of approximately 1 g/mol.
- Therefore, the molar mass of NH₃ = 14 + (3 × 1) = 14 + 3 = 17 g/mol.
- The molar mass of nitrogen gas (N₂) is:
- N₂ = 2 × 14 = 28 g/mol.
- Since 17 g/mol (NH₃) is less than 28 g/mol (N₂), Statement-1 is true.

**Step 2: Evaluate Statement-2**
- Statement-2 states that at a given temperature, the rate of diffusion is inversely proportional to the square root of its density.
- This statement is a reflection of Graham's Law of Effusion/Diffusion, which states that the rate of diffusion of a gas is inversely proportional to the square root of its molar mass (and thus density, since density is related to molar mass).
- Therefore, Statement-2 is also true.

**Step 3: Determine the relationship between the two statements**
- Although both statements are true, Statement-2 does not provide a correct explanation for Statement-1. Statement-1 is a factual statement about the molecular masses, while Statement-2 relates to diffusion rates.
- Therefore, the correct conclusion is that both statements are true, but Statement-2 is not a correct explanation of Statement-1.

**Final Answer:**
- The answer is Option B: Statement-1 is true, Statement-2 is true, but Statement-2 is not a correct explanation of Statement-1.

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