Ice to water

[naple]

I have always thought about this and ended up getting confused. Lets say you take ice and break it to two pieces, if you want to make it one piece again you can't unless u melt it then freeze it again. I would like to understand why does changing it to liquid enables us to reform the bondings. I want to know what happens between the bondings and atoms ( deep explanation )

 

Thanks

[Phi for All]

Is this for homework?

 

What is happening to change ice to water? How are the molecules being affected?

[naple]

Its not a homework, i got curious about it. You didn't understand my question. It is basically.....for example: you can make two liquid water droplets join but not two small ice pieces. liquid will attract other water droplets but doesn't happen for ice.

[Phi for All]

The molecules in water are much more active than in ice due to more heat. They're moving around and changing position relative to each other. When water on the surface of the two pieces of ice interact and then the heat is removed by freezing, the molecules slow down and form a pattern that locks them together.

 

Water molecules have a different pattern when frozen than most liquids, a pattern that makes them take up more space than when they were liquid. That's why ice expands rather than contracts like most liquids do when they form frozen patterns.

[michel123456]

I have always thought about this and ended up getting confused. Lets say you take ice and break it to two pieces, if you want to make it one piece again you can't (...)

 

You should make the experiment.

Take 2 blocks of ice from your refrigerator with your hands and place them touching side by side, they will make a solid block.

If you take them out with a spoon, they probaly won't.

[skwiff]

if you press two peices of ice together they stick...

[Chap]

Well, simple explanation is that ice has a fixed lattice structure (unique, but still a lattice) while water doesn't. Water molecules are able to move (a bit) and hence they are able to interact more closely. Once you break the ice, the lattice structure is broken. In breaking the lattice structure, you are re-arranging the lattice. So the two parts of the original lattice becomes foreigners to each other.For example, when you break an ice cube, the force you apply causes the atoms to get nearer to each other. This causes strong repulsion between the positively charged nuclei to take place. This repulsion forces the bonds holding the lattice to break, hence causing the ice to break up. The laws of chemistry dictates that the lattice structure should be preserved, so the only way to preserve the structure after breaking up is through rearrangement; thus making the two pieces foreigners.

 

And by the way, ice will only stick when you press them together because the ice melts at the point of contact due to the pressure that you apply. So they will actually be interacting as water molecules and refreezing (when you release the pressure), rather than the two solids annealing together.

 

Hope this answers the question?

Edited December 7, 2011 by Chap