An inflated ballon has a volume of `0.55 L` at sea level `(1.0 atm)` and is allowed to rise to a height of `6.5 km` , where the pressure is about `0.40 atm`. Assuming that the temperature remains constant , what is the final volume of the ballon ?
Strategy : We know the volume at one pressure and want to know the volume at another pressure keeping temperature constant. This suggests the use of Boyle's law. We tabulate what is known and what is asked for and then solve Boyle's law equation for the unknown quantitu `V_(2)`.

Explanation

We have
`{:("Initial conditions",,,"Fi nal conditions",),(p_(1) = 1.0 atm,,,p_(2) = 0.40 atm,),(V_(1) = 0.55 L,,,V_(2) = ?,):}`
Solving Boyle's law equation `(5.6) for V_(2)` and substituting gives
`V_(2) = V_(1) xx (p_(1))/(p_(2))`
`= 0.55 L xx (1.0 atm)/(0.40 atm)`
`= 1.4 L`