Physic Labs

Problem 2

One mole of monatomic ideal gas initially at T0=300 KT_0=300\,\mathrm K and volume V0=2.0 LV_0=2.0\,\mathrm L is heated in a cylinder with a freely moving piston, so the gas pressure remains constant throughout. The gas expands to 2V02V_0. Assume quasistatic equilibrium, neglect piston friction, and use R=8.31 J/(mol K)R=8.31\,\mathrm{J/(mol\,K)}. (a) Find the final temperature and gas pressure. (b) Calculate the work done by the gas and its change in internal energy. (c) Find the heat transferred to the gas and state its sign.
pf=p0,Tf=2T0=600 Kp_f=p_0,\qquad T_f=2T_0=600\,\mathrm K
problems.proof.analysis

At constant pressure, pV=RTpV=RT implies that temperature is proportional to volume. Doubling the volume therefore doubles the absolute temperature.