Boyle's law
An inflated balloon occupies a volume of 2.0 L the balloon is tied with a string and weighted with a heavy stone. What is its volume when it reaches the bottom of a pond 20.8 m deep? Note: One atmosphere of pressure supports a column of water 10.4 m high. Assume the pressure acting on the balloon before it submerges is 1.0 atm.
P1 = 1 atm
P2 = 1 + 2 = 3 atm
V1 = 2 L
P2 V2 = P1 V1
V2 = (1/3)*2 = 2/3 L