Saturated Solutions

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Q1. At 20 °C, the solubility of KCl is 34 g/100 g of H2O. In the laboratory, a student mixes 75 g of KCl with 200. g of H2O at a temperature of 20 °C.
a. How much of the KCl will dissolve?
b. Is the solution saturated or unsaturated?
c. What is the mass, in grams, of any solid KCl left undissolved on the bottom of the container?
Q2. At 40 °C, the solubility of KNO3 is 65 g/100 g of H2O. How many grams of KNO3 will dissolve in 120 g of H2O at 40 °C?
a. At 20 °C, KCl has a solubility of 34 g of KCl in 100 g of water. Using the solubility as a conversion factor, we can calculate the maximum amount of KCl that can dissolve in 200. g of water as follows:
b. Because 75 g of KCl exceeds the maximum amount (68 g) that can dissolve in 200. g of water, the KCl solution is saturated.
c. If we add 75 g of KCl to 200. g of water and only 68 g of KCl can dissolve, there is 7 g (75 g − 68 g) of solid (undissolved) KCl on the bottom of the container.

[@Raul28153]

I am struggling here pal. Why not simply figure out what the common multiplier is ( in this case it is 2) and multiply by that???
Does this more convoluted multiply by 200 then divide by 100 have some redeeming quality when the underlying problem is different?

[@StudyForceOnline]

There are more than 1 way to do this. You could find the percentage of 34/100, which is 34 percent, and multiply that (or 0.34) with 200 g to see if it exceeds 75 g.

[@Raul28153]

@@StudyForceOnline Be nice ~!!! I wanted to know why you chose that way.

[@StudyForceOnline]

@@Raul28153 Looking back, I'd probably do it differently