Question

An unknown volume of gas has a pressure of 0.50 atm and temperature of 325 K. If the pressure is raised to 1.2 atm and the temperature decreased to 320 K, giving a new volume of 48 L, what was the initial volume?
A. 65 L
B. 87 L
C. 120 L
D. 140 L

Answer 1

You can solve this by using the equation (P1V1/T1) = (P2V2/T2). Plug in 0.50 atm for P1, leave V1 as the unknown, and plug in 325 K as T1. Then substitute 1.2 atm for P2, 48 L for V2, and 320 K for T2. Solve for V1, which is 117L, but since you round using two sig figs, your answer is C, 120 L. Hope this helps!