A gas has a pressure of 710 kPa at 227°C. What will its pressure be at 27.0°C, if the volume doubles?

1 Answer
Jun 15, 2017

"Final Pressure" = 213Final Pressure=213 "kPa"kPa

Explanation:

We're asked to calculate the final pressure of the gas, given its change in temperature and the fact that its volume doubled.

We can solve this problem using the combined gas law:

(P_1V_1)/(T_1) = (P_2V_2)/(T_2)P1V1T1=P2V2T2

We must convert our given temperatures to Kelvin, which we always must do for gas equations:

T_1 = 227^"o""C" + 273 = 500T1=227oC+273=500 "K"K

T_2 = 27.0^"o""C" + 273 = 300T2=27.0oC+273=300 "K"K

We're not given any values for the volume, but we know that V_2V2 is twice that of V_1V1, let's make things as simple as possible by making V_1V1 11 liter and V_2V2 22 liters.

Plugging in our known values, and rearranging the equation to solve for the final pressure, P_2P2, we have

P_2 = (P_1V_1T_2)/(T_1V_2) = ((710"kPa")(1cancel("L"))(300cancel("K")))/((500cancel("K"))(2cancel("L"))) = color(red)(213 color(red)("kPa"

The final pressure is thus color(red)(213 kilopascals