Determining the Chemical Formula of a Hydrate
PROCEDURE
Experiment required: copper (II) sulfate hydrate, 2 crucibles, electronic mass balance, bunsen burner, iron ring, crucible tong, clay triangle, wire gauze, retort stand,
1. Individuals should wear goggles on and tied hair back before the experiment started.
2. The mass of an empty crucible cover was measured.
3. Approximately 2.00g of copper (II) sulfate hydrate samples was taken out and put into the crucible.
4. The mass of the crucible cover and copper (II) sulfate hydrate samples was measured.
5. The heating apparatus were set up as instructed, such as bunsen burner, retort stand, iron ring and clay triangle. The crucible was put on the clay triangle, and then the bunsen burner was …show more content…
After the reaction completed, the bunsen burner was turned off. The hot crucible was taken down by the tong and was placed on the wire gauze. The crucible would take some times to cool down until people can touch it safely.
7. The mass of the crucible cover and copper (II) sulfate sample was measured.
8. Step 1-5 were repeated one more time, and the data were recorded again.
9. All the remained wastes were put into the garbage bag, and the crucible was cleaned up by the soap. All the equipments were put back into the equipment box.
Table of Observed Mass for the Reaction of CuSO4.XH2O Mass of CuSO4.XH2O(g) Mass of CuSO4 and crucible cover(g) Mass of crucible cover(g) Mass of CuSO4 (g)
1st time 2.00 44.05 42.77 44.05-42.77=1.28
2nd time 1.27 43.57 43.57-42.77=0.80
OBSERVATION RESULTS
ANALYSIS
1. a) The percent by mass of water in copper(II) sulfate hydrate.
1st experiment: %H2O=mwatermCuSO4.XH2O = 2.00g-1.18g2.00g=41.00%
2nd experiment: %H2O=mwatermCuSO4.XH2O=1.27g-0.81g1.27g=36.22%
Average: (41.00% + 36.22%) ÷ 2=38.61%
b) Yes, I expect the percent by mass that I calculated to be similar to the percent by mass that other groups calculated. Since every group calculate the same compound, which would have the same amount of molar mass and …show more content…
5. a) If I did not completely convert the hydrate to the anhydrous compound, the mass percent of water in the compound would be less than it should be, because there would be some water remained in the copper (II) sulfate. So, the mass percent of water would decrease, because the mass of water decrease; the mass percent of copper(II) sulfate would increase, because the mass of copper(II) sulfate increase.
b) The x value of water in the chemical formula would be lower.
6. a) The calculated mass percent of water in the compound would be more than it should, if the hydrate was lost as it spatters out of the container. Because if the hydrate was heated too quickly, the water would be evaporated quickly too, and the part that was lost would be mostly copper (II) sulfate. When the copper (II) sulfate was lost, the mass of copper(II) sulfate decrease, therefore mass percent of copper(II) sulfate would decrease. Also, the mass percent of water in the compound would increase, because there is less copper(II) sulfate.
b) The x value of water in the chemical formula would be
PROCEDURE
Experiment required: copper (II) sulfate hydrate, 2 crucibles, electronic mass balance, bunsen burner, iron ring, crucible tong, clay triangle, wire gauze, retort stand,
1. Individuals should wear goggles on and tied hair back before the experiment started.
2. The mass of an empty crucible cover was measured.
3. Approximately 2.00g of copper (II) sulfate hydrate samples was taken out and put into the crucible.
4. The mass of the crucible cover and copper (II) sulfate hydrate samples was measured.
5. The heating apparatus were set up as instructed, such as bunsen burner, retort stand, iron ring and clay triangle. The crucible was put on the clay triangle, and then the bunsen burner was …show more content…
After the reaction completed, the bunsen burner was turned off. The hot crucible was taken down by the tong and was placed on the wire gauze. The crucible would take some times to cool down until people can touch it safely.
7. The mass of the crucible cover and copper (II) sulfate sample was measured.
8. Step 1-5 were repeated one more time, and the data were recorded again.
9. All the remained wastes were put into the garbage bag, and the crucible was cleaned up by the soap. All the equipments were put back into the equipment box.
Table of Observed Mass for the Reaction of CuSO4.XH2O Mass of CuSO4.XH2O(g) Mass of CuSO4 and crucible cover(g) Mass of crucible cover(g) Mass of CuSO4 (g)
1st time 2.00 44.05 42.77 44.05-42.77=1.28
2nd time 1.27 43.57 43.57-42.77=0.80
OBSERVATION RESULTS
ANALYSIS
1. a) The percent by mass of water in copper(II) sulfate hydrate.
1st experiment: %H2O=mwatermCuSO4.XH2O = 2.00g-1.18g2.00g=41.00%
2nd experiment: %H2O=mwatermCuSO4.XH2O=1.27g-0.81g1.27g=36.22%
Average: (41.00% + 36.22%) ÷ 2=38.61%
b) Yes, I expect the percent by mass that I calculated to be similar to the percent by mass that other groups calculated. Since every group calculate the same compound, which would have the same amount of molar mass and …show more content…
5. a) If I did not completely convert the hydrate to the anhydrous compound, the mass percent of water in the compound would be less than it should be, because there would be some water remained in the copper (II) sulfate. So, the mass percent of water would decrease, because the mass of water decrease; the mass percent of copper(II) sulfate would increase, because the mass of copper(II) sulfate increase.
b) The x value of water in the chemical formula would be lower.
6. a) The calculated mass percent of water in the compound would be more than it should, if the hydrate was lost as it spatters out of the container. Because if the hydrate was heated too quickly, the water would be evaporated quickly too, and the part that was lost would be mostly copper (II) sulfate. When the copper (II) sulfate was lost, the mass of copper(II) sulfate decrease, therefore mass percent of copper(II) sulfate would decrease. Also, the mass percent of water in the compound would increase, because there is less copper(II) sulfate.
b) The x value of water in the chemical formula would be