Question
Problem 1. Peter pours 750g of water over ice in a cup. Determine the amount of heat lost by the water of temperature 40°C as it melts 100g of ice of temperature-5°C (Lusion = 333 J/g). At the time the ice has completely changed its state to liquid (but before the thermal equilibrium) what is the temperature of the water that was poured into the cup? What is the final temperature of the water poured and water from melted ice as they reach thermal equilibrium? The specific heat of water is 4.181/g The specific heat of ice is 2.11 J/g
Explanation / Answer
Qloss = Qgain = Mice*Cice*dT1 + Mice*Lf
Qloss= (100*2.110*5)+(100*333)
Qloss = 34355 J
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Qloss = Mwater*Cw*dT
34355 = 750*4.18*(40-t)
t = 29 degree
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in equilibrium heat lost = heat gain
Mwater*Vwater*(29-t) = Mice*Cwater*(t-0)
750*4.18*(29-t) = 100*4.18*t
t = 25.6 degrees