IV. First Law of Thermodynamics Chapter 19 The First Law: AE, =W +0. The work done on a gas (the system): W =-["pal/" . Ideal gas processes are Isochoric, Isobaric, Isothermal, Adiabatic. The molar specific heat C of a substance is the energy needed to raise the temperature of 1 mol by 1 K, O=nCAT . 1 atm = 105 Pa = 10 N m. The ideal gas law is pl =ART and R =8.314 J mol"K". The specific heat of water is 4184 J K kg. A rigid balloon with walls made of thin graphene and with negligible heat capacity has an internal volume of & L containing only He gas at 12.5 atm pressure at an initial temperature of 300 K. (a) How many moles, n, of He are in the balloon? (b) The balloon is immersed in liquid neon at a temperature of 27 K. What is the new pressure of the gas in the balloon in atmospheres? (c) What is the final temperature Ty (in K) of the gas when the balloon at 27 K is removed in thermal isolation from the liquid Ne and thermally coupled to an insulated 100 cm' = 0.1 kg water bath initially at a temperature of 300 K and comes to thermal equilibrium with the bath