A balloon initially contains 25 L of helium gas at 100 kPa and 22 °C. The balloon is connected by a valve to a line supplying He at 150 kPa and 25 °C. The valve is opened, and He enters the balloon until the pressure of He inside the balloon reaches 150 kPa. The balloon is made of a material such that its volume increases linearly with its pressure (i.e., P = k . V, where k is a constant). If the process is fast enough so that we can neglect the heat transferred from/to the system, determine the final temperature of He inside the balloon.
Assume that He behaves as an ideal gas with constant specific heats:
ˆHe ˆ Cv =3.1156kJ (kgK) ; RHe =RHe MHe =2.0769kJ (kgK) ; MHe =4.003kg kmol.