Answer
a) $3.876\ kJ/K$
b) $-3.434\ kJ/K$
c) $0.441\ kJ/K$
Work Step by Step
From tables A-11 to A-13
Initial ($P_1=200\ kPa, x_1=0.4$): $v_1=0.04043\ m^3/kg,\ u_1=112.76\ kJ/kg,\ s_1=0.4678\ kJ/kg.K$
Final ($P_2=400\ kPa, v_2=v_1$): $x_2=0.7853,\ u_2=172.02\ kJ/kg,\ s_2=0.62920\ kJ/kg.K$
Mass: $m=V/v,\ V=0.5\ m^3$
$m=12.37\ kg$
a) $\Delta S_{sys}=m(s_2-s_1)=3.876\ kJ/K$
b) $Q=m(u_2-u_1)=1058\ kJ$ (in)
$\Delta S_{src}=-\frac Q{T_{src}},\ T_{src}=308\ K$
$\Delta S_{src}=-3.434\ kJ/K$
c) $\Delta S= \Delta S_{sys} + \Delta S_{src}$
$\Delta S=0.441\ kJ/K$
