Question

Particle-level diagrams
create particle-level diagrams showing the particle’s relationship to other particles according to the phase they are in for two of the following three situations:

bubbles of gas form as pasta water begins to boil on the stove
a refreshing drink contains both ice cubes and water
freeze-drying technology dehydrates foods through sublimation
That is my assignment^
I don't understand what I'm supposed to draw exactly. If someone could give me an example, of what it would look like, without actually doing my homework for me, that would be great.
Thanks

Answer 1

If you can't think of an example, you can use the sublimation example I listed, because I won't be doing that one - I'll do the two others.

Answer 2

I'll describe the sublimation example. What you do when you freeze-dry something is that you first cool it down, so if there is water in some food for example, this water is becomes ice. Then you take away the air around what you want to freeze-dry, this reduces the pressure a lot. The boiling point of water drops when you reduce pressure, so when you drastically reduce pressure to almost zero it eventually drops below the temperature of the frozen food. This effectively makes the solid ice in the food "boil" or sublimate, it becomes a gas without first becoming a liquid.

We could describe this process using a picture of water-molecules as particles, so you could for example first draw water molecules in a crystal structure with air particles above it which keeps the water particle in a crystal. Then you could draw another picture with no air particles and some water particles escaping the crystal going in all directions like a gas, this is what happens when water sublimates.

Answer 3

Wow thanks a lot!
I now understand how I can do this assignment!

Answer 4

In case you're wondering, here's the evaporation example I drew