Table 4: Data for Unknown Hydrate Table 4 Mass of a crucibl e and lid Mass of crucibl e, lid, and hydrat e Heati ng time of cycle 1 Cooli ng time of cycle 1 Mass of crucibl e, lid, and residu e Heat ing time of cycl e 2 Cool ing time of cycl e 2 Mass of crucibl e, lid, and residu e cycle 2 Heat ing time of cycl e 3 Cool ing time of cycl e 3 Mass of cruci ble, lid + resid ue cycle 3 Trial 1 31.579 g 33.660 g 15 min 15 min 33.224 g 15 min 15 min 3.227 g N/A N/A N/A Trial 2 19.167 g 23.343 g 15 min 15 min 20.892 g 15 min 15 min 20.900 g N/A N/A N/A Table 4: The data recorded here is of an unknown hydrate. The purpose of this data is to make it possible to find out what the hydrate is. The mass of the crucible + lid, crucible + lid + hydrate, crucible + lid + residue, and the length of the heating and cooling cycles are recorded here. The residue is what is left of the hydrate after it has gone through a heating and cooling cycle. There was not enough time for the 3rd cycle. Data from Table 4, Column 3 and 2, Trial 1: Mass of crucible, lid, and hydrate - Mass of crucible and lid= Mass of hydrate: 33.660 g - 31.579 g = 2.080 g Trial 2: 23.343 g - 19.167 g = 2.176 g Data from Table 4, Column 6 and 2, Trial 1: Mass of crucible, lid, and residue - Mass of crucible and lid= Mass of residue
33.224 g - 31.579g = 1.645 g Trial 2: 20.900 g - 19.167 g = 1.725 g Results Table 1: Mass of Unknown Hydrate Mass of hydrate Mass of residue Mass of water lost Trial 1 2.080 g 1.645 g 0.436 g Trial 2 2.176 g 1.725 g 0.451 g Table: The mass of the unknown hydrate, residue, and water lost are recorded here after being calculated from the data obtained in Table 4: Data for Unknown Hydrate. The difference was found between the mass of the crucible + lid and crucible + lid + hydrate to find the mass of the hydrate for each trial. The difference was found between the mass of the crucible + lid + residue at the end of cycle 2 and the mass of the crucible + lid which is the mass of the residue. The difference between the mass of hydrate and the mass of residue is the mass of water lost. Data from Results Table 1 Mass of hydrate - Mass of residue = Mass of water lost Trial 1: 2.080 g - 1.645 g = 0.436 g Trial 2: 2.176 g - 1.725 g = 0.451 g Results Table 2: Hydrate Ratio Initial moles of salt + waters of hydration Exact calculation of mole ratio of salt to water Empirical formula for hydrate Trial 1 s= 0.012 w= 0.024 1 mole CaSO 4 *2 mol H 2 O CaSO 4 *2H 2 O
Trial 2 s= 0.013 w=0.025 1 mole CaSO 4 *2 mol H 2 O CaSO 4 *2H 2 O Table: After the mass of the unknown hydrate and its anhydrous form was found that data was used to figure out what the unknown hydrate was along with its moles, mole ratio, and empirical formula. The hydrate was discovered to be CaSO 4 * 2H 2 O.
You've reached the end of your free preview.
Want to read all 8 pages?