Given an initial volume of 10,500 liters and initial temperature of 15 C, final temperature of -25 C, and assuming that the gas inside the balloon is an ideal gas:
Ideal Gas Law:
nRT = PV
assume that the number of moles and pressure are constant, the equation becomes
V/T = constant
V1/T1 = V2/T2
Substituting given conditions, solve for V2:
10,500L/ (15+273) = V2/ (-25 + 273)
V2 = 9041.67 L
