If you fill a glass with ice cubes to the top, then fill the same glass with water until one more drop and it will over flow. When the ice melts will the glass over flow the sides of the glass?
This reminds me of a skill that one of my Brother-in-laws was so proud of. His ability to pour a shot-glass of tequila to overflow without spilling a drop, or even a micro-drop. He loved to demonstrate; yes, you can overfill without spilling thanks to the cohesive molecules that hold together before surrendering to gravity. If you stop pouring at a precise instant there will be a slight bulge at the surface, which can be observed by laying the side of one's head on the bar surface and you can actually see the the bulge or crown that rises slightly above the rim of the shot glass.
But that was only half of the skill.
The other half was to chug it without spilling a drop. While he almost always succeeded in accomplishing the first, this second skill was more hit-or-miss, mostly miss. But he always gave it 4 or 5 attempts before his wife made him quit.
Im pretty sure the answer to this is NO it will not over flow because ice takes up space in the glass which is called diplacement so as the ice melts (returns to its liquid form) it just takes the place of the ice (its solid form) since ice is just water in a solid form as it returns to a liquid form its just replacincing the space it took up as a solid rather it fills in the now empty space that it took up as a solid , or something like that. RIGHT
@Highonheels You are correct. The melting ice releases the trapped air reducing the total volume of the ice thus giving more room for the liquid water. The glass will not over flow.
But the it isn't the same quantity of water, even if you made an exact bit of ice which you could completely slide into the glass. Why? Well, see (for instance) @PhoenixPhail's answer, but you already know this.
Ask yourself if ice sinks or "swims"...?
It floats, right? So H2O is an oddball substance which EXPANDS when it freezes: a given mass of water goes UP in [u]volume[/u] when it freezes, so the [u]density[/u] (mass per unit volume) goes DOWN.
So the
(density of ice) < (density of liquid water)
which is why it floats.
AND why a glass even [u]completely[/u] full of ICE has FEWER H2O molecules than the [i]same[/i] glass when it is [u]completely[/u] full of liquid water.
It's a great question to make people think, and to which we all know the answer, if we just stop and think about a drink with ice.
cold shrinks heat expands.. simple i like science also.. math is just a fact.. grin mark but it seem like not with water.. reading the comments below..
No. The density of ice is less than the density of water
ρ_{ice} < ρ_{water}
so, as the ice melts, it decreases in volume. Even if you fill the glass entirely with ice, the melted ice will not overflow the glass.
It might be easier to see if one considers it in reverse: if the glass were full of water, then frozen, the ice would expand and go over the upper edge of the glass. So the quantity "water frozen in ice which is only to the edge of the glass" is clearly less than the quantity "water up to the edge of the glass which is then frozen in ice".
@black4white yes if you fill a glass with water then add ice yes it will overflow but the question states that you fill the glass with ice first then add water , since the ice creates a displacement of the water the melting ice just fills in the place that it took as a solid.
@clark1234 It's Physics, not Maths; but it is an intriguing question because water does have some very strange properties for such an unassuming, simple, commonplace but vitally necessary compound!
No one seems to have taken account of the fact that some of the ice will be above the water level so the level may rise as this melts. Would like a scientists view on this. We know the total mass will be less.
@4185philip yes, the ice will float in the water. As the ice melts the entrapped air is released, the volume of the container with not increase so no water will be spilled from the glass.
@turbineman40 It won't overflow even if the ice and water contain no air because the density of pure ice is lower than the density of pure water which means that the ice displaces an equal mass of water but smaller volume (the ice will float) so when the ice melts to match the water temperature it will occupy less space.