The pressure of a given mass of a gas changes from 200Nm-2 to 120Nm-2 while the temperature drops from 127°C to -73°C. The ratio of the final volume to the ...

The pressure of a given mass of a gas changes from 200Nm-2 to 120Nm-2 while the temperature drops from 127°C to -73°C. The ratio of the final volume to the initial volume is

Answer Details

P1 = 300Nm-2; P2 = 120Nm-2
T1 = 127 + 273; T2 = -73 + 273
= 400K; = 200K

Let the initial volume V1; and the final volume = V2

∴ P1V1/T1 = P2V2/T2
P1V1T2 = P2V2T1
∴ V2/V1 = P1T2/P2T1
∴ V2/V1 = (300 x 200)/(120 x 400) = 5/4

∴ V2 : V1 = 5 : 4