In general, when a pure substance or mixture goes from liquid to solid, the molecules in it get closer resulting in a higher density.

If this is so why does ice float in water?

I'm not sure whether this is real or something invented in the desperation of a chem final, but when water freezes, the molecules, due to the interaction of the 120-degree bond angles, forms hexagons, with enpty space in between. That's also believed to be the reason mature snowflakes always have six arms.

.O.O
O...O
.O.O

Ignore the little periods. I couldn't get the flooble thing to accept multiple continguous spaces.

Posted by banerd on 2003-08-01 16:39:42