A helium balloon with a volume of 1m^3 and temperature of 27 deg c is placed in liquid nitrogen in an open container and cools to a temperature of 77 K. Assume that helium behaves like an ideal gas at constant atmospheric pressure and find the new volume of the gas in the balloon, the change in internal energy of the gas, the work done during the process, and the heat removed from the gas.
i got the new volume=.257m^3
and i got the work with constant pressure=73400J
but i can't get the internal energy and the heat
The Attempt at a Solution
I attempted to find the number of moles and then find the mass to plug it into Q=mct to find Q, but I am not getting the correct answer. Please help