What is the volume of the gas at the lower temperature?

Question

A weather balloon containing helium with a volume of 410 L rises in the atmosphere and is cooled from 27 degrees celsius to -27 degrees celsius. The pressure is reduced from 110 KPA to 25 KPA.

Answer 1

P1 * V1 / T1 = P2 * V2 / T2

 

P1 = 110 kPa

V1 = 410 L

T1 = (27+273)K = 300K

 

P2 = 25 kPa

V2 = ?

T2 = (-27+273)K = 246K

 

V2 = (P1/P2) * (T2/T1) * V1 = (110 kPa / 25 kPa) * (246K / 300K) * (410 L) = 1479 L