Question

A balloon contains 5L of oxygen at a pressure of 90 kPa. How much oxygen will the ballon contain if the pressure is lowered to 67 kPa.

Answer 1

1- According to this formula:
P1V1 = P2V2

2-By converting P from KPa to atm:
1 KPa = 0.00986923267 atm
So,
P1= 0.888231 atm
P2 = 0.661239 atm

by substitution on the previous formula:
P1V1 = P2V2
0.888231 x 5 = 0.661239 x V2
So,
V2(for the oxygen will the ballon contain) = 6.7 L