Question

A balloon occupies a volume of 1.25 L at sea level where the pressure is 760 mm Hg. What volume would the balloon occupy at an altitude of 35,000 ft where the air pressure is only 220 mm Hg ?

Answer 1

The formula to be adopted is P1V1 = P2V2

P1 = 1 atm (which is 760 mm Hg)

V1 = 1.25 L

P2 = 220 mmHg = 220 mmHg x (1 atm / 760 mmHg) = 0.289 atm (converting mmHg to atm)

V2 = ? L

V2 = P1V1 / P2

= 1 atm x 1.25 L / 0.289 atm

= 4.33 L