# Physics/chem

posted by on .

Trying to beat the heat of summer, a physics grad student went to the local toy store and purchased a child's plastic swimming pool. Upon returning home, he filled it with 154 liters of water at 25°C. Realizing that the water would probably not be cool enough, he threw ice cubes from his refrigerator, each of mass 28 g, into the pool. (The ice cubes were originally at 0°C.) He continued to add ice cubes until the temperature stabilized at 19°C. He then got in the pool.

The density of water is 1000 kg/m3, the specific heat of water is 1.0 cal/g °C, the specific heat of ice is 0.5 cal/g °C, and the latent heat of fusion of water is 80 cal/g.

How many ice cubes did he add to the pool to get the temperature to 19°C? (Consider the pool and ice cubes an isolated system.)
Physics - bobpursley, Saturday, November 20, 2010 at 4:06pm
The sum of heats added is zero.

Help:

n*masscube*Lf+n*masscube*Cwater*(19-0)+masswater*Cw(19-25)=0

mass water= densitywater*154liters=154kg

solve for n.

I've tried to do this from the help above, but I am still not getting the right answer.

• Physics/chem - ,

check your units, make certain all units are in SI (cal/g) is not SI.