Notes:
- H¬2O, Copper Sulfate, Starch
- H2O (water)- liquid, solvent, boiling point: 100 C, freezing point: 0 C.
- Copper Sulfate- solid, soluble, forms an aqueous solution, is a salt.
- Starch- solid, macromolecule (long chain sugar), not very soluble in water at low temperatures.
- When H2O, Copper Sulfate, and starch are mixed together, it forms a heterogeneous mixture.
- Aqueous solution of copper sulfate with a suspension of starch.
Research Question: What effect does the use of the separation techniques of filtration for the separating of the starch and evaporation for separating the water, have on the mass of the remaining substance, copper sulfate?
Hypothesis: If a mixture of water, copper sulfate, …show more content…
Mass of copper sulfate and tare weight of the beaker – Mass of 100 mL beaker = Mass of copper sulfate 53.84g – 50.89g = 2.95g The mass of the copper sulfate is 2.95g.
3. Mass of starch and tare weight of filter paper – Mass of the filter paper = Mass of starch 3.46g – 0.50g = 2.96g The mass of the starch is 2.96g.
4. Mass of water / Mass of Mixture #6 x 100% = Percent of water 32.68g / 38.59g x 100% = 84.68% The percent of water in the mixture is 84.68%.
5. Mass of copper sulfate / Mass of Mixture #6 x 100% = Percent of copper sulfate 2.95g / 38.59g x 100% = 7.64% The percent of copper sulfate in the mixture is 7.64%.
6. Mass of starch / Mass of Mixture #6 x 100% = Percent of starch 2.96g / 38.59g x 100% = 7.67% The percent of starch in the mixture is 7.67%.
Graph:
Evaluation: Percent error of the experiment was 4.2% for the mixture, 8.9% error for obtaining the water, 41% error for obtaining the copper sulfate, and 48% error for obtaining the …show more content…
The copper sulfate made up 7.64%. Some factors that might have affected the experiment were the limited time that was available for this experiment and that my mixture started with a mass of 38.56 grams instead 37 grams. The time affected the experimental results because the filtration process took longer than expected to filter through the filter paper. Therefore when the starch was put into the dryer oven, there was also water and copper sulfate remaining in the starch. This copper sulfate contamination of the starch is why the dried starch was observed to have a greenish color instead of the predicted yellow. If there was more time in the class period, then the masses of the substances would be closer to the correct amount that was given. This also would have prevented the greenish color of the starch and the very small amount of copper sulfate that was obtained by the end of the experiment. The inaccurate mass of Mixture #6 also affected the results because since the original mass of this mixture was supposed to be 37 grams and the theoretical amount were 38.59 grams. This affected the masses of the substances in the mixture as well. Instead of obtaining 30 mL of water, 5 grams of copper sulfate, and 2 grams of starch, the theoretical amounts of each substance was 32.68 grams or mL of water, 2.95 grams of copper sulfate, and 2.96