67.0 L
Explanation:
Step 1: Given data
Moles of C₃H₈: 2.99 molPressure: 1 atm (standard pressure)Temperature: 273.15 K (standard temperature)
Step 2: Calculate the volume occupied by 2.99 moles of C₃H₈ at STP
C₃H₈ is a gas. If we assume ideal behavior, 1 mole of C₃H₈ at STP occupies 22.4 L.
2.99 mol × 22.4 L/1 mol = 67.0 L