00:01
Okay, so in this particular question, we're given the scenario of liquid water turning into solid ice and what's going on with certain things as far as kinetic energy, potential energy, heat, whether it's endo or exothermic, and what's going on with the system and its surroundings.
00:20
So i went ahead and put up the stair step diagram again, where the y -axis is the temperature, x -axis is simply the progression of adding heat or removing.
00:30
Moving heat.
00:32
And again, we're going from liquid to solid.
00:34
So we're going down the stair step.
00:36
Now, going down the stair step entails that we're releasing energy from the system to its surroundings.
00:43
So recall that when going from solid to liquid or liquid to gas, we're actually putting heat in to break those intermolecular bonds and separate those molecules.
00:53
Well, the opposite is true when we're going down the stair step.
00:56
So we're going from a liquid to a solid.
00:59
And that means we are releasing heat into the surroundings.
01:04
So in this case, we have an exothermic scenario, and the surroundings are gaining that heat...
