Law of Def. Composition
...ble, cover, and magnesium. Record it on the Report Sheet. 5. Set up the ring stand, ring, Bunsen burner, and pipestem triangle as shown in Figure A. Place the crucible in the pipestem triangle. Begin heating the crucible gradually with the lid completely on. Heat slowly by moving the flame around underneath the crucible. Remove the heat temporarily if a large amount of smoke comes out of the crucible. 6. After about four minutes of direct heating with no smoke, remove the lid. Continue to heat the crucible for 8 more minutes. 7. Turn off Bunsen burner and put the lid back in the crucible. Allow the crucible to cool to a temperature low enough so that you can touch the crucible. Find the mass of the crucible, contents, and cover. Record the mass on the Report Sheet. 8. Add ten drops of distilled water. Smell cautiously, noting and odor. Set up crucible for heating again. Reheat for four more minutes with the lid on. Let the crucible cool once again. 9. Find the mass of the crucible, cover, and product. Record in on the Record Sheet. 10. Compare the masses found in steps 7 and 9. If the masses do not agree within 0.03g, reheat the crucible for four minutes, cool, and find the mass. Repeat until the last two masses agree within this range. 11. Before leaving the laboratory, clean up all materials and wash your hands thoroughly. Data and Observations: Data Table 1 Mass of crucible and cover 17.09g Mass of crucible, cover, and magnesium 17.3g Mass of crucible, cover, and product1st time (before adding water) 17.68g Mass of crucible, cover, and product2nd time unaccomplished Mass of crucible, cover, and product3rd time unaccomplished After adding the distilled water, there was an odor observed. Data analysis: 1. The mass of the magnesium that reacted. 17.3g - 17.09g = .21g 2. The mass of the magnesium oxide that was produced. 17.68g - 17.09g = .59g 3. The mass of oxygen that reacted. .59g - .21g = .38g 4. The ratio of the mass of magnesium to the mass of oxygen. .21g/.38g = .55g 5. The accepted ratio for the mass of magnesium to the mass of oxygen is 1.52. Calculate your percent error using the formula: (Experimental value - Accepted valu...