How do you separate iron, naphthalene, polyethylene, urea, and sand?

Question

this mixture is in the dry, solid form

Answer 1

(1)
pull the iron out by using a magnet. Its the only substance in your mixture that will be attracted to a magnet.

(2)
Put the mixture in water. the sand will settle to the bottom, it is not soluble in water and is dense. The polyethylene has a density less than 1.0 , so it will float. Slim it off the top of the water.

(3)
The Naphthalene is also insoluble in water , filter out the sand and naphthalene , (save the solution for use in step # 4) Use a nonpolar solvent to disolve the Naphthalene, then recrystalize it by low temperature and vacume methods. Naphthalene sublimates at room temperature. After all the Naphthalene has been collected, dry the sand.

This can be done in a beaker..

(4) The urea is soluble in water, so you can evaporate the water and reclaim the urea.

before you begin check the densities, and vaporization temperature for the substances.

the density of polyethylene is less than 1.0g/ml see :

http://plastics.dow.com/plastics/na/prod/polyethylene/hdpe.htm

http://en.wikipedia.org/wiki/Naphthalene

http://en.wikipedia.org/wiki/Sublimation_%28physics%29

Answer 2

Send them to their rooms, and no TV privileges for the rest of the day! Dad Has Spoken!

Magnet for the Iron, Heat for the naphthalene, water to float off the polyethylene, and I'll get back to you when I figure the Urea angle.

Answer 3

You're going to have to be a lot more specific. Are they solids? Aqueous ions (not the sand)? Is the iron in a compound?