ice-water density

[HugoP]

The density of ice is less than that of water and therefore ice floats on water. What other substances behave like this?
Thanks, HugoP

[JudgeJ]

Water begins to expand when the temperature falls below 4 degrees Celcius and upon freezing to ice, its volume is about 9% greater than liquid water.

I believe this property of expansion on freezing is unique to water.

It also has a number of other strange or unexpected properties. Its melting and boiling points are considerably higher than would be expected when compared to other compounds with similar properties.

It also has a relatively high specific heat value which makes the oceans a useful "battery" for storing the energy given out by the Sun. The sea (or indeed rivers and lakes) take considerably longer to heat up and cool down than the land does, and this has a profound effect on the Earth's climate.

All in all, handy stuff!

[Whickerman]

Poo does.

[stoo_pid]

No other liquid behaves like that. For something that we take for granted water is really quite amazing stuff. If you're interested, this link is a bit basic but gives you a bit more info

[newtron]

Apparently, both gallium and bismuth are less dense in their solid form than in their liquid forms.

http://encarta.msn.com/encyclopedia_761571486_2/Liquid.html

[gastwo]

Whickerman - it does, and it doesn't - the specific gravity depends on your diet. Floaters/sinkers etc.

(though I suspect you were being 'faececious'...)

[elginsmarble]

If you find this property of water interesting, read into the properties of liquid helium around the lambda point.

Freaky.