"x" L of methane gas at STP contains `1.5xx10^(21)` molecules. The number of molecules in "x" L of sulphur diocide at STP will be :

Options

A. `3xx10^(21)`
B. `1.5xx10^(21)`
C. `6xx10^(21)`
D. `0.15xx10^(21)`

Explanation

To solve the problem, we need to determine the number of molecules in "x" liters of sulfur dioxide (SO₂) at standard temperature and pressure (STP), given that "x" liters of methane (CH₄) contains \(1.5 \times 10^{21}\) molecules.

### Step-by-step Solution:

1. **Understand the Conditions**:
- We are given that both methane and sulfur dioxide are at STP (Standard Temperature and Pressure).
- STP conditions imply a temperature of 273.15 K and a pressure of 1 atm.

2. **Apply Avogadro's Law**:
- Avogadro's Law states that equal volumes of gases at the same temperature and pressure contain an equal number of molecules.
- Since both gases are at STP and occupy the same volume "x", we can use this law.

3. **Identify the Given Information**:
- Methane (CH₄) in "x" liters contains \(1.5 \times 10^{21}\) molecules.

4. **Conclusion Based on Avogadro's Law**:
- Since the volume of methane and sulfur dioxide is the same and the conditions are identical, the number of molecules in "x" liters of sulfur dioxide will also be \(1.5 \times 10^{21}\).

5. **Final Answer**:
- Therefore, the number of molecules in "x" liters of sulfur dioxide (SO₂) at STP is \(1.5 \times 10^{21}\).

### Summary:
The number of molecules in "x" liters of sulfur dioxide at STP is \(1.5 \times 10^{21}\).

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