chemistry volume

Question

If I have 21 liters of gas held at a pressure of 78 atm and a temperature of 900. K, what will be the volume of the gas if I decrease the pressure to 52 atm and decrease the temperature to 750 K?

Answer 1

Given:

Initial volume = V1 = 21 liters

Initial pressure = P1 = 78 atm

Initial temperature = T1 = 900K

Final pressure = P2 = 52 atm

Final temperature = T2 = 750K

Asked for:

Final volume = V2 = ?

Use the combined gas law:

P1V1/T1 = P2V2/T2 and solve for V2 ...

V2 = P1V1T2 / P2T1 = (78)(21)(750) / (52)(900)

V2 = 26.25 liters = 26 liters (2 sig. figs.)