Question

What is the amount of heat released when 0.8 kg of water at
25°C cools until it becomes ice at –6°C? State the assumptions
you make in your calculations.

Answer 1

Answer:

Total heat produced = heat from water cooling + heat from change of phase+heat from ice cooling.

Heat from cooling = heat capacity of material*mass*change in temperature

Heat from phase change = m*L, where m is mass in kg; L is the specific latent heat for material => 336000 J/kg for ice

Then,

Heat released = 4200*.8*24+.8*336000+2000*.8*6 = 84000+268800+9600 J

Heat released: 362400 J