A weather balloon is filled with 0.295 m3 of helium on the ground at 18 °C and 756 torr.

What will the volume of the balloon be at an altitude of 10 km where the temperature is
48 °C and the pressure is 0.14 atm?

1 answer

since PV=kT, PV/T is a constant.

So, using the given numbers,

(.14 atm)V/(271+48) = (756 torr)(.295)/(271+18)

You will need to reconcile atm and torr, and then solve for the new V