Heat Thermodyna...

A Carnot’s engine works as a refrigerator between 250 K and 300 K. If it receives 750 calories of heat from the reservoir at the lower temperature, the amount of heat rejected at the higher temperature is

2 kg of ice at –20ºC is mixed with 5 kg of H₂O at 20ºC in an insulating vessel having negligible heat capacity. Calculate the final mass of water left in the container. Given specific heats of water and ice are 1 kcal kg–1_ºC–1 and 0.5 kcal kg–1_ºC–1 and latent heat of fusion of ice is 80 kcal kg^–1.