A sample of dichloromethane gas (CH₂Cl₂) occupies 32.6 L at 310 K and 5.30 atm. Determine its volume at STP?

• A. 145 L
• B. 150 L
• C. 320 L
• D. 350 L
• E. 390 L

Answer: (B)

Verified step by step guidance

1. Identify the initial conditions of the gas: the initial volume (V1) is 32.6 L, the initial temperature (T1) is 310 K, and the initial pressure (P1) is 5.30 atm.
2. Recognize that STP (Standard Temperature and Pressure) conditions are defined as 0°C (273.15 K) and 1 atm pressure. Therefore, the final temperature (T2) is 273.15 K and the final pressure (P2) is 1 atm.
3. Use the combined gas law to relate the initial and final states of the gas: \( \frac{P1 \cdot V1}{T1} = \frac{P2 \cdot V2}{T2} \). This equation allows you to solve for the final volume (V2) at STP.
4. Rearrange the combined gas law equation to solve for V2: \( V2 = \frac{P1 \cdot V1 \cdot T2}{T1 \cdot P2} \). Substitute the known values into this equation.
5. Calculate the final volume (V2) using the rearranged equation. Ensure that all units are consistent and perform the arithmetic operations to find the volume at STP.