00:01
Okay, this is chapter 11, section problem 68.
00:04
And the question is, how much ice in grams would have to melt to lower the temperature of 352 milliliters of water from 25 degrees celsius to 5 degrees celsius? and we can assume the density of water of 1 gram per millimeter.
00:19
And the whole idea here is that the amount of energy released from the decrease in temperature by the water has to be equal and opposite to the amount of energy absorbed by the ice melt.
00:31
So that's essentially q is equal to, you know, q is equal to q.
00:35
And the only other equation really that we need here is that q is equal to m -cat.
00:39
So the heat is going to be equal to the mass times a specific heat times the delta t.
00:44
And we need two constants here, the specific heat of the liquid water, which is 4 .184 joules per gram per degrees celsius.
00:52
And the heat of fusion of the ice, which is 334 joules per gram.
00:58
You might also be able to look this up as 6 .02 kilojoules per mole, but since we're working in grams here, we can just stick with that one.
01:06
So our starting place here is the volume of liquid water...