With a 2-fold decrease in the gas volume, the pressure increased by 120 kP

With a 2-fold decrease in the gas volume, the pressure increased by 120 kPa, and the absolute temperature increased by 10%. What was the initial pressure?

Problem data: V1 (initial volume) = 2V2; ΔР (increase in gas pressure) = 120 kPa; ΔT (increase in absolute temperature) = 10% (T2 = 1.1T1).

To find the initial pressure of the taken gas, we use the proportion: P1 * V1 / T1 = P2 * V2 / T2.

Substitute the known values: P1 * 2V2 / T1 = (P1 + ΔP) * V2 / 1.1T1.

P1 * 2 = (P1 + ΔP) / 1.1.

2 * 1.1 * P1 = P1 + ΔP.

2.2P1 – P1 = ΔP.

P1 = ΔP / 1.2 = 120 / 1.2 = 100 kPa.

Answer: The initial pressure of the taken gas was 100 kPa.