Properties of Hydrates Essay

PurposeThe innovation of the Properties of Hydrates lab is to study hydrates, and be able to identify them. This lab also focuses on observing the reversibility of hydration reactions by hydrolysis, and also shielding substances for efflorescence of deliquescence.ProcedureA.Identification1. Place 0.5 grams of each mingled (Nickel Chloride, Potassium Chloride, Sodium Tetraborate, Sucrose, Calcium Carbonate, and Barium Chloride) in a humble dry block out tube. 2. Heat gently with a burner flame and mark c arefully. If droplets of piss appear on the test tube it may be a hydrate. Note the nature and vividness of the residue. 3. Let the tube quiet, and pronounce to dissolve the residue in a few cm3 of piss, warming if necessary. A true hydrate will dissolve in water, producing a discolor similar to that of the received hydrate. A carbohydrate will give absent water, but tends to char. The residue will also often be a caramel color.B.Reversibility1. Gently heat a few crysta ls of about 0.3 grams of render Cobalt(II) Chloride, CoCl2 x 6H2O in an evaporating yellowish pink until the color change appears to be hit 2. Dissolve the residue in the evaporating dish in a few cm3 of water from the wash bottle 3. Heat the residue to a boiling and carefully boil it to dryness. Note any color changes. 4. charge the evaporating dish on the lab bench and let it cool.C.Deliquescence and Efflorescence1. Place a few crystals of Na2CO3 x 10H2O, CaCl2, KAl(SO4)2 x 12 H20, and CuSO4 in an a remove evaporating dish next to the CoCl2 prepared in embark on B. 2. To see put up the samples gained or lost mass, weigh each of them on a top-loading poise and record to the nearest hundredth. 3. Weight them over again after an hour to discover ANY changes in mass. 4. Observe the samples occasionally. Note any structures in color and structureand degree of wetness.D. Percent of Water in Hydrate1. not bad(p) crucible and its cover, and also make sure that crucible pair of tongs are clean. Put over fire, and let cool. 2. Weight the crucible to the nearest thousandth. Handel with tongs 3. Obtain a sample of an unknown hydrate, and place about 1 gram in the crucible. 4. Weight the crucible, cover and sample on the balance. 5. Put the crucible on the clay triangle, with the cover off center to accord water vapor to escape. 6. Heat again, gently at first, and and then with the croup red for about 10 minutes. 7. Center the crucible cover, and let it cool to room temperature. 8. Weight the cooled crucible and with its cover and contents. 9. Examine the solid residue.10. lead water until the crucible it 2 thirds full. Warm gently if the residue doesnt readily dissolve. 11. Does the residue appear to be soluble?Waste organizationDispose of the Copper mixture, and the Aluminum mixture in the correct till under the waste hood. All of the acids and bases can be disposed of shovel in the sink. If the compound isnt water soluble put in the constitution al container.Chemical Principles in the Laboratory Experiment 6ConclusionThe purpose of the Properties of Hydrates lab was to be able to identify if a substance was a hydrate or not. In lab, experiments where conducted to see if a compound was a hydrate or not. In order for the compound to be deemed as a hydrate it had to1. Release water upon heating2. The anhydrous residue had to be water soluble3. Exhibit reversibilityIf, and only if the compound showed that it could break all three of theseproperties, could it be distinguished a hydrate. In begin A of the experiment, Nickel Chloride and Sodium Tetraborate were the only two compounds that were true hydrates. twain of these showed water residue when heating, where soluble in water after heating, and reborn back to it original color after performing the first two experiments. Some of the other compounds had positive results for one or two test but not all three. For example, Sucrose, when heated, water residue appeared on the te st tube, and was soluble in water, but the compound didnt show reversibility.In part B of the experiment, CoCl2*6H2O was heated, dissolved, and then heated again to show that it was a true hydrate. When the Cobalt Chloride was heated, it turned from the color of fuchsia pink, to a light blue. And then after existence dissolved into water, the compound turned back to its original color of fuchsia pink, demonstrating reversibility. The color change in this compound shows that by adding water to the anhydrous residue, that the same bonds that were broken my dehydrating the compound where reformed when adding water.In part C, four compound, plus the Cobalt Chloride mentioned above were tested for deliquescence, and efflorescence. save one compound turned about to be efflorescent, which means that it lost water, which was Sodium Carbonate. The compounds mass before sitting out was 50.645g, after being exposed to the conditions of the laboratory for an hour, the sample weight 50.603g lo sing approximately 0.042g over the plosive of an hour. The Calcium Chloride (gained 0.258g), Copper Sulfate (gained 0.007g) and Cobalt Chloride (gained 0.068g) where all deliquescent, meaning that again mass while sitting in the laboratory. The Potassium Aluminum sulfate, exhibited constancy while sitting out for an hour, neither gaining nor losing mass.For part D of the experiment, the per centum of water in the unknown hydrate was %12.290. The closet percent of the presumption details of the unknown was Barium chloride (BaCl2*2H2O), which has %14.8 water in it. This percent was found by using the formula below % water in hydrate=(mass of water in hydrate/mass of the entire hydrate)The wide range of distinction between the percent of the given and the unknown could prepare been due to the fact that there was wood debris in the unknown sample . This could have thrown off the amount of water present in the sample, and messed up the amount of water able to evaporate.