Question

A 200.0-mL sample of helium gas is in a cylinder with a movable piston at 110 kPa and 275 K. The piston is pushed in until the sample has a volume of 95.0 mL. The new temperature of the gas is 310. K. What is the new pressure of the sample? a)51.1 kPa b)261 kPa c)249 kPa d)274 kPa

Answer 1

Option B. 261 KPa.

Step-by-step explanation:

From the question given above, the following data were obtained:

Initial volume (V1) = 200 mL

Initial pressure (P1) = 110 kPa

Initial temperature (T1) = 275 K.

Final volume (V2) = 95 mL

Final temperature (T2) = 310 K

Final pressure (P2) =?

The new pressure (P2) can be obtained by using the following formula as illustrated below:

P1V1 /T1 = P2V2 /T2

110 × 200/275 = P2 × 95/310

22000 / 275 = P2 × 95/310

80 = P2 × 95/310

Cross multiply

80 × 310 = P2 × 95

24800 = P2 × 95

Divide both side by 95

P2 = 24800/95

P2 = 261 KPa.

Thus, the new pressure of the gas is 261 KPa.