how can you separate sand from water and calculate the percent composition (using chemistry terms)

Answer 1

Weigh the mixture to get total mass

Filter the mixture. Sand stays on the filter paper, water comes through.

Dry the sand and weigh to find mass of dry sand

mass dry sand/total mass of original mixture (x100) = % composition of sand by mass

Answer 2

Hi Jas B.,

A little bit of a misleading directions, I'd say! This task is "physical science", just heat the sand/water mixture to distill off and condense the water. Then cool the sand, so that the next student doesn't burn him-/herself on it. There's no chemistry to it, except the recognition that the two substances can be so treated.

I guess you could also centrifuge the sand, to essentially do the same, but with much greater expense and hazard.

If you wanted to throw some chemical terms into it, you could point out that the water so separated usually carries no warning labels (as a lab chemical), but that the sand is labeled extensively as a respiratory inhalation hazard. In fact, it has about the most extensive warning labeling of any lab chemical I've ever dealt with, which is saying a lot!

-- Cheers, -- Mr. d.