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Purpose: Do different solids have different solubility points?
Materials:
balance massing cups 2 test tubes scoopula
stirring rod burner graduated cylinder white solids
goggles 2 No 2 stoppers test tube rack
2 evaporating dishes
Procedure
1. Put 5 cm3 of water in two different test tubes.
2. Dissolve 5 grams of two solids in each tube, stopper
3. Shake it for several minutes until the solution is saturated
4. If tube cools, warm it with your hand
5. Compare data with other students
6. Pour all solution into a pre-massed evaporating dish (make sure not to put any undissolved solid in dish )
7. Slowly evaporate the saturated solution to dryness over flame
8. Be careful not to heat quickly or solid will splatter… blue flame away.
9. To find concentration evaporate the liquid from known mass of solution subtract the mass of the remaining dry solution from the mass of the solution (the volume of the water in your sample)
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