> 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?

The water level will remain constant, because the mass of water in the system (liquid water+ice) is constant.

Under the hypothesis of atmospheric pression and room temperature the dispersion as vapor is not relevant.

The ice displaces an amount of water of the same weight (Archimede's law). Since ice has 9/10 of the density of water, the cube will float and emerge for 1/10 of its height.

As the ice cube melts, water level will remain constant because the increase in volume of liquid water is compensated by the less water displaced by the lighter ice cube.

AP (out of chemistry issues since 1986... :) ).