CSCAPrep
Reviewed CSCA Chemistry question · Standard

A 2.50 L flask contains 0.150 mol of an ideal gas at a pressure of 1.20 atm. What is the temperature of the gas in degrees Celsius? (R = 0.0821 L·atm·mol⁻¹·K⁻¹)

  1. -29°C
  2. 244°C
  3. 29°C
  4. 517°C
Show the answer and explanation

Correct answer

A. -29°C

Principle or equation

Ideal gas law: PV = nRT. Solve for T in kelvin, then convert to Celsius by subtracting 273.15.

Why this answer is correct

T = PV / (nR) = (1.20 atm × 2.50 L) / (0.150 mol × 0.0821 L·atm·mol⁻¹·K⁻¹) = 3.00 / (0.012315) ≈ 243.6 K. Convert to Celsius: 243.6 - 273.15 = -29.55°C ≈ -29°C.

Example

For 0.200 mol in 4.00 L at 1.00 atm, T = (1.00 × 4.00)/(0.200 × 0.0821) = 243.6 K = -29°C.

This published item includes a stored explanation and passed the platform’s publication workflow. It is independent preparation material, not a claim of an official or recalled examination question.

Related practice questions