A cylinder is fitted with a piston and is in thermal contact with a heat bath at 273 K. Initially the volume in the cylinder is filled with 10 kg of pure water and about half of this is liquid and other half is solid. The piston is lowered so as to reduce the volume by 2 x 10^-5 m^3. What is the magnitude and sign of heat transferred to the bath.
Density of liquid water 10^3 kg/m^3, density of ice 0.92 x 10^3 kg/m^3, latent heat of fusion of ice 333 kJ/kg.