w=-pv=nRT=-2kJ,得T=2/R；由单原子理想气体可知Cv,m=3/2*R;等压下的理想气体有Cp,m-Cv,m=nR,得Cp,m=5/2*R由Cp,m=Q/T得Q=Cp,m*T=5/2*R*2/R=5KJ，即吸热为5KJ
