# how come ice floats on water?

do they not weigh the same?

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• eri
Lv 7

When ice freezes, it forms a crystalline structure that is less dense than water. So it floats.

Same volume of ice and water

DO NOT WEIGH THE SAME.

A 1 liter container of ice weighs less than a 1 liter container of liquid water, and the lighter material floats to the top.

When ice forms, it takes up about 9% more space than it did as a liquid. Thus, a 1 liter container of ice weighs less than a 1 liter container of liquid water, and the lighter material floats to the top. As we said, water is different.

• Mike
Lv 5

Water is pretty weird stuff. We think of it as normal because it is so plentiful, but it's behavior is very different from most substances. Because of the way the two hydrogen atoms bond to the oxygen atom, water is polar, that is the charge is not evenly distributed. At temperatures near freezing the molecules all want to line up plus pole to minus pole similar to the way magnets all want to line up north pole to south pole. The thing is that the molecules don't fit together as tightly when lined up this way as they do when they are moving faster and don't have time to line up with each other. So water that is above freezing has more closely packed molecules than in ice where most of the molecules are lined up. Water is more dense than ice. Ice floats.

Water is one of the few liquids that expands when freezing. Therefore a given volume of ice weighs less than an equal volume of water. So it floats.

As stated by everyone here, ice is less dense than water.

This is for a variety of reasons that all relate back to one basic property of water that makes it unusual: water is a polar molecule.

Polar molecules have a slightly positive end and a slightly negative end. This means that one water molecule is attracted to another water molecule.

A simply way to see this for yourself is to look at a drop of water on a counter top. Bend down so that you are at eye level with the counter and you will see that the water makes a bubble. This is caused because the water is attracted to itself (wants to hang on to one another, rather than spread out).

Do the same thing with some rubbing alcohol from the medicine cabinet...no bubble. Why? Alcohol (and most other liquids that are not water) are non-polar, and therefore not attracted to themselves. Instead the alcohol simply spreads out flat.

Onto the ice.

As things cool down they condense closer and closer together. This is true of almost all things. In fact, even water will become more dense as it cools....until it reaches around 3 celsius at which point it starts to expand and become less dense. This expansion is also caused by the polarity of water.

As the water molecules slow down (cooler objects move slower than warmer objects) enough the polarity of molecules force it into the hexgonal shape that was mentioned in another post.

The key is that water is a polar molecule.

• Anonymous
4 years ago

Ice is way less dense than water because of the unique structure of H2O (2 in subscript). In liquid form, the hydrogen bonds between adjoining H2O molecules are consistently forming and reforming, which potential the gap in between the molecules is continually being crammed by diverse molecules as move takes position. inspite of the indisputable fact that, even as water freezes, the H2O molecules are stuck in a lattice structure, and the areas between the molecules are literally not consistently being crammed. This leads to what the previous 2 solutions have suggested - ice having a decrease density then water. it truly is a Chem and in no way a Physics answer, by ways. XD

When water turns into ice, it is less dense. The density of Ice is less than the density of water. So if floats