> For goodness sake - I definitely need it (chemistry help, that is). I am in Chem 102 at my college and was wondering if anyone could help me out with a couple of things.
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> We are studying "Chemical Equilibrium" now. We have to write a paragraph by Friday explaning what would happen to this system: A cube of ice is placed in a beaker and water is poured in until the level of the water is at the very top of the beaker. (The ice will be sticking about 1/3 of the way out of the water.) The beaker is at room temperature. So, the question is: What happens to this system as the ice melts?
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> Here is what I know so far: Ice is less dense than water, so as the ice cube melts the water level will fall. But I am also thinking (since we are studying equilibria) that it has something to do with the water vapor also. Our professor didn't tell us if the beaker was covered or not, so I'm not exactly sure what will happen to the system as vapor is produced. Also I don't know the point at which vapor will start to form - I have a feeling that we need to know this.
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> Ga"any help would be so totally appreciated"halia

Okay, I'm not chemistry expert, but I took some chemistry classes and am fairly familiar with basic physics and the properties of water. Here's what will happen, if I'm totally right:

First of all, it is important to remember that you are correct that ice is less dense than water. Also, take into consideration how much less dense it is, exactly. But more important to remember is this: water, in any form and regardless of volume, will weigh the same as long as the mass remains constant. This is important because we can recall that when something floats in water it is displacing an amount of water equal in weight to the object floating. Basically what I'm saying is this. The ice floating in the water would take up the exact same space as the hole created in the water by the ice cube because it weighs the same as the amount of water(and therefore in liquid form IS the same volume as the amount of water)that would be occupying that space. So as the ice melts the water level will not change.

Shan-C'mon, Junior Chemistry, don't fail me now!-dar