'Limiting Reagents Lab Essay\r'

'Problem: What messiness of fall result form when 1.69g of CuCl2.2H20 reacts with 1.31g of aluminium?\r\n eyeshot 3: Materials:\r\n> cl mL beaker\r\n> Erlenmeyer Flask\r\n> 100ml Graduated Cylinder\r\n> move;\r\n> Scoopula\r\n> Electronic Balance\r\n> Stir Rod\r\n> aluminium Foil\r\n> CuCl2.2H20\r\n> Distilled Water\r\nProcedure:\r\nDay 1\r\n> Rinse beakerwith distilled water.\r\n> battalion 1.69g of CuCl2.2H2O.\r\n> Add to beaker and add 50mL of distilled water.\r\n> great deal aluminum. Fold in 1/2 & adenine; coil loosely.\r\n> Place in beaker and let turn on overnight.\r\nDay 2\r\n> Pull out aluminum and rinse into beaker\r\n> Mass dawn root word, put call on it\r\n> Put paper in funnel and funnel into the Erlenmeyer flas.\r\n> Pour in mixture. Rinse beaker trinity times.\r\n> Rinse funnel and paper twice.\r\n> Remove physical composition and let dry overnight.\r\nDay 3\r\n> Mass filter paper\r\n infor mation Collection and affect (DCP)\r\nAspect 1: Recording Raw Data:\r\nMass of CuCl2.2H2O †1.93g\r\nMass of Al †? (The push-down storageing of the aluminum was forgotten)\r\ndata-based mass of precipitate = .69g\r\nAspect 2: bear upon Data\r\n2Al(s) + 3CuCl2.2H2O â€> 3Cu(s) + 6H2O(l) + 2AlCl3(aq)\r\nm Al=1.93g\r\nM Al= 26.98 g/mol\r\nm 3CuCl2.2H2o = 1.69 g\r\nM 3CuCl2.2H2o = 152.47 g/mol (Chem 20 Data Booklet)\r\nm Cu = ?\r\nn CuCl2.2H2O = 1.93g / 170.49 g/mol\r\nn CuCl2.2H2O = .011320312 mol\r\n3 mol CuCl2.2H2O = 3 mols Cu\r\nn Cu = .011320312 mol\r\nm Cu = .011320312 mol x 63.55 g/mol\r\nm Cu = .719g\r\n% yield = .69 / .719 = 96%\r\nAspect 3:\r\nExperimental mass of Cu(s) precipitate = .69g\r\nTheoretical mass of Cu (s) precipitate = .719g\r\n% yield = 96%\r\n inference and Evaluation (CE)\r\nAspect 1: Conclusion: The mass of precipitate that forms when 1.93g of CuCl2.2H20 reacts with 1.31g of aluminum is .69 g. The % yield was 96%. The massing of aluminum was f orgotten but when another piece was massed and the numbers were worked out, it was shown that there was an excess of aluminum and that the CuCl2.2H2O was the limiting reagent.\r\nAspect 2: Evaluate: There were .029g of Cu precipitate less than expected. It is likely that some of the copper went into the Erlenmeyer or was stuck on the funnel. Despite thorough rinsing of the filter paper, some of the precipitate got through the filter paper and into the Erlenmeyer.\r\nAspect 3 Improving Experimental form: Instead of one piece of filter paper, twain pieces should be used. This would lead to less precipitate waiver into the Erlenmeyer. Also, the water in the Erlenmeyer could be re-filtered.\r\n'