Question

A closed weather balloon with an initial volume V rises up in the atmosphere to a point where the outside air pressure is 1/10 of the pressure at sea level and the temperature of the air has dropped by a factor of 3. Assume that the balloon is filled with an ideal gas and that the material of the balloon exerts no pressure and does not insulate so that the temperature and pressure are the same inside and outside the balloon. Do the volume and internal energy of the gas increase, decrease, or stay the same as the balloon rises? Justify your answer.

Answer 1

PV = nRT

Step-by-step explanation:

the balloon is closed so n is constant

R is constant

If the temperature was constant, a tenfold decrease in pressure would cause a tenfold increase in volume

If the pressure was constant, a threefold decrease in temperature would result in a threefold decrease in volume.

In this situation, the pressure change overwhelms the temperature change so the volume and internal energy both increase