Solubility Equilibrium and the Effect of Temperature Essays

1208 Words May 30th, 2005 5 Pages
Introduction For this experiment, we are going to determine the effect of temperature on solubility, to be done in a chemical by dissolving a solute in a definite amount of solution which is saturated. Specifically, the goal of this experiment is to prepare a saturated solution of Na2C2O4 in water at different temperatures, determine the effect of temperature in solubility, and to apply Le Chatelier's Principle. We can do all this by simply titrating a certain amount of standard KMnO4, and measuring how much KMnO4 was needed to help Na2C2O4 reach chemical equilibrium at certain temperatures. In doing this, we will have fulfilled all the goals of our experiment, as well as being able to determine the Solubility of Na2C2O3 at both 20 and …show more content…
I then added 50 ml of distilled to the test tubes A1, B1, C1 and D1, then titrated them with the potassium permanganate solution (making sure to add 15 ml 3M sulfuric acid in each), then recorded the amount it took for them to turn pink.
Data
A. Standardization of KMnO4 solution:
Sample g Na2C2O4 moles Na2C2O4 (x 10^-3) moles KMnO4 (x 10^-3) ml KMnO4 used M KMnO4
#1 .47 3.51 1.4 15.5 .090
#2 .50 3.73 1.5 16 .093
Average M = .091
B. Solubility of Na2C2O4 at different temperatures: in M and g/ L.
Sample and temp (C): ml of KMnO4 titrated moles KMnO4 (x 10^-4) moles NaC2O4 dissolved (x 10^-3) M (moles/L) Na2C2O4 g Na2C2O4 dissolved in sample g / L Na2C2O4
A1 – 3 5.0 4.55 1.14 .228 .152 30.5
B1 – 31.1 6.0 5.46 1.37 .274 .183 36.6
C1 – 45 8.8 8.01 2.00 .400 .268 53.7
D1 - 80 9.5 8.65 2.16 .432 .290 57.9

Solubility of Na2C2O4 in g / L Experimental Value in g / L Handbook Value in g / L
At 20 C 36 37
At 100 C 73 63.3

C. Relationship of K and ∆H
Sample Average M of Na2C2O4 K=[Na^+]^2[C2O4] ln K T K 1 / T K (x 10^-3)
A1 .228 .047 -3.05 276 3.62
B1 .274 .082 -2.50 304.1 3.29
C1 .400 .256 -1.36 318 3.14
D1 .432 .322 -1.13 353 2.83
At 20 C .276 .084 -2.48 293 3.41
At 100 C .472 .421
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