STATEMENT-1 : Wet air is heavier than dry air.
STATEMENT-2 : The density of dry air is less than the density of water at 1 atm and 273K.

Options

A. If both the statement are TRUE and STATEMENT-2 is the correct explanation of STATEMENT-1
B. If both the statement are TRUE but STATEMENT-2 is NOT the correct explanation of STATEMENT-1
C. If STATEMENT-1 is TRUE and STATEMENT-2 is FALSE
D. If STATEMENT-1 is FALSE and STATEMENT-2 is TRUE

Answer

To analyze the given statements, we will break down the information step by step.

### Step 1: Understanding the Statements
- **Statement 1**: Wet air is heavier than dry air.
- **Statement 2**: The density of dry air is less than the density of water at 1 atm and 273K.

### Step 2: Determine the Molecular Weights
1. **Molecular Weight of Dry Air**:
- The average molecular weight of dry air is approximately 28.9 g/mol.

2. **Molecular Weight of Water**:
- The molecular weight of water (H₂O) is approximately 18 g/mol.

3. **Molecular Weight of Wet Air**:
- Wet air contains water vapor. To find the average molecular weight of wet air, we consider the contribution of both dry air and water vapor.
- The molecular weight of wet air can be calculated as:
\[ \text{Molecular Weight of Wet Air} = \frac{(28.9 \text{ g/mol}) + (18 \text{ g/mol})}{2} = 23.5 \text{ g/mol} \]
- However, this calculation is not entirely accurate as it does not consider the proportion of water vapor in the air. Instead, we should note that the presence of water vapor (which is lighter than dry air) reduces the overall average molecular weight of the air mixture.

### Step 3: Compare the Densities
1. **Density of Dry Air**:
- The density of dry air at standard conditions (1 atm and 273K) is approximately 1.29 kg/m³.

2. **Density of Water**:
- The density of water at the same conditions is approximately 1000 kg/m³.

### Step 4: Analyze the Statements
- **Statement 1 Analysis**:
- Wet air is actually lighter than dry air because the presence of lighter water vapor decreases the average molecular weight of the air mixture. Therefore, **Statement 1 is false**.

- **Statement 2 Analysis**:
- The density of dry air (1.29 kg/m³) is indeed less than the density of water (1000 kg/m³). Therefore, **Statement 2 is true**.

### Conclusion
- **Final Evaluation**:
- Statement 1: False
- Statement 2: True
- The correct option is that Statement 1 is false and Statement 2 is true.