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Q & A: Paper Suspensions

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Most recent answer: 10/22/2007
Q:
Paper is a solid. If I blend it in a blender with water, is it a liquid? A solution? My mom says it’s a suspension. What is that? Help!!!
- Cena (age 10)
Amerman, Northville
A:
Cena -

Sounds like your mom's got the right idea. What you've got isn't a liquid or a solution, it's a suspension. To get a liquid from your solid, you'd have to heat the paper up until it melted (hard to do, since it'd probably burn first). The difference between a solution and a suspension is a bit trickier.

In a solution, the molecules in the thing you're adding (the solute) actually get mixed up with the molecules of the thing you're adding it to (the solvent). Once they're mixed, they're hard to separate without boiling. An example of this would be if you mixed some salt into water. The salt crystals actually break apart into separate atoms and molecules and get mixed up with the water molecules.

In a suspension, the molecules don't actually get mixed up. It's more like there's large-ish chunks (particles) of a solid just floating around in the liquid. If you let it sit for a while, the solid particles will settle to the bottom. An example of this is if you mixed sand with water. The sand wouldn't break down into molecules and mix with the water - it would just float around in it. And eventually, it would settle to the bottom. Paper in water is the same way.

-Tamara

(published on 10/22/2007)

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