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Hello, I am trying to do the Saturated Solutions: Measuring Solubility activity. I understand both methods, but what I don't understand is how to calculate the solubility from the second method.

Second method:
1. Label the underside of each saucer with tape, one for each solution.
2. Weigh the empty saucer and record the weight.
3. Pour in 10-15 mL of the appropriate saturated solution (corresponding to the label on the saucer).
4. Weigh the saucer + solution and record the weight.
5. Repeat steps 2-4 for each of the three solutions.
6. Put the saucers in a warm place (e.g., an oven on low heat) and allow the water to evaporate.
7. Re-weigh the saucers + dry crystals.

Some help would be super appreciated! Thanks!


[Administrator note: Project: https://www.sciencebuddies.org/science- ... solubility ]

Hello,

With Method 2 you'll need to do some subtraction to calculate the mass solid and the mass/volume of the liquid. These can be used to calculate the solubility of the solution just like Method 1.

Mass of solid = (mass of saucer with dry crystals) - (mass of saucer)
Mass of liquid evaporated = (mass of saucer with wet solution) - (mass of solid calculated above) - (mass of saucer)
Remember 1 g of water is equal to 1 ml.

Hope this helps!

Audrey