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A young girl is carrying a spherical helium balloon of diameter 32 cm home from

ID: 1589244 • Letter: A

Question

A young girl is carrying a spherical helium balloon of diameter 32 cm home from a carnival at the beach on a 25 degree C day. What is the volume of the balloon? How many moles of helium are in the balloon if the pressure inside the balloon is 2.0 atm? She lets the balloon go and it rises high in the atmosphere. Assuming no helium leaks out of the balloon, what is its volume when the atmospheric temperature is 40 degree C and the atmospheric pressure is 0.1 atm. Is this a realistic calculation or will the balloon pop from too much expansion?

Explanation / Answer

a) Volume = 4/3 pi r^3 = 4/3 *3.14* (0.16)^3 =0.01715 m^3

b) PV=nRT

n=PV/RT=2*0.01715 /8.314*298 =1.38e-4 moles

c) V= RT/P = 8.314*313/0.1= 26022.82 m^3

d) The Ballon will Pop from too much expansion