How is water different from most other substances when it freezes?
Answers
Answer:
One of the weirdest aspects of water is its unusual density. Normally, liquids become increasingly dense as they are cooled down, but water reaches a maximum density at about 4 degrees Celsius (39.2 Fahrenheit).
Below this point it is less dense, so when it freezes and becomes ice at 0 degrees Celsius (32 Fahrenheit), the ice is less dense than the water. This is why water ice floats, and bodies of water freeze from the top down.
But that's not all. Water also has really high surface tension - aside from mercury, it has the highest surface tension of all liquids. This is what allows water spiders to skate across the top.
To top it all off, water also has an unusually high boiling point, and the fact that so many chemical substances dissolve in it is also really peculiar, if we compare it to other liquids.