Question

Five kilograms of water at 40◦C is poured on a large block of ice at 0◦C. How much(in Kg) ice melts ?


Hf = 335 kJ/kg

cw = 4.184 kJ/(kg·◦C

Answer 1

Sum of heats gained=0
since you know the final temp will be water at 0C, you dont have to worry about the unmelted ice. You can verify that with the solution.
heat lost by water +heatgainedbyice meleting=0
5kg*SpecHeatwater*(40-0)- MassIcemelted*335 =0

solve for massIceMelted.

Answer 2

80

Answer 3

2.5