Formula Of Hydrate Lab Report

The purpose of this lab is to determine the formula of an unknown hydrate. To achieve this, we heated a hydrate over a Bunsen burner to drive out the water. As a result, the anhydrate is left and the data is used to calculate the mole ratio between the amount of anhydride and water. Then the mole ratios are used to calculate the hydration number, which was 4.8, but was rounded to 5 in the formula. The accepted formula is 〖CuSO〗_4∙5H_2 O and the percent of error was 4%.

This experiment is based on determining the chemical formula for a hydrated compound containing copper, chloride, and water molecules in the crystal structure of the solid compound, using law of definite proportion. The general formula of the compound is CuxCly•zH2O, and aim is to determine chemical formula of this compound.

As a group, we obtained our salt mixture of calcium chloride and potassium oxalate, and weighed the mixture. We were able to make an aqueous solution from the mixture and distilled water. We boiled and filtered off the solution, leaving the precipitate. Once the precipitate was dried overnight, it was weighed and the mass was measured. Then we calculated the moles of the precipitate.

The mass of the water was found by subtracting the original mass of the hydrate by the anhydride, that was found after heating the hydrate and evaporating the water. However, if the hydrate was not fully heating and there was still excess water remaining, this excess water mass would be included in the anhydride mass. This would make the mass of the anhydride larger and the mass of the water smaller. If the mass of the water was smaller, then the amount of moles of water would also be smaller. The mole ratio of anhydride to water would be larger because the denominator in the ratio, water in this case, would be smaller, so the entire ratio would essentially increase. This would mean that the number of molecules of water would be smaller as a result.

Put approximately 9-10(g) copper ore into beaker. Use spatula to break up any large pieces. Next add 17ml H2SO4 (aq) (hydro sulfuric acid) to the beaker. Began mixing until all or most traces of blue dissipate; or the copper ore will no longer dissolve (should appear as a milky liquid). Next use pipette to and remove solution and divide solution into 2 individual test tubes then Place test tubes into centrifuge and run centrifuge for 1 minute. Remove from centrifuge machine Fill a cuvette with the clear solution from the test tube making sure not to disturb the sediment at the bottom. Note the solution should bluish in tint Final place the cuvette in the colorimeter. Then record data and calculate in results section.

The mass percent of water was determined using the mass of water and dividing it by the total mass of the hydrate and then multiplying that answer by 100%. The number of moles of water in a hydrate was determined by taking the mass of the water released and dividing it by the molar mass of water. The number of moles of water and the number of moles of the hydrate was used to calculate the ratio of moles of water to moles of the sample. This ratio was then used to write the new and balanced equation of the dehydration process. The sample was then rehydrated to the original state and the percent of the hydrate recovered was calculated by using the mass of the rehydrated sample by

The powdered cobalt oxalate hydrate was weighed to about 0.3 g and placed in a pre-weighed crucible. The crucible and the cobalt oxalate were then heated until the cobalt oxalate decomposed into a stable, black solid, or Co3O4. Once the crucible was sufficiently

4. Take a piece of dialysis(as cut earlier), find the mass of the dialysis, and the zero out the scale on

Unknown I was weighed 3 times in a graduated cylinder with 20 mL of water in it. Weight 1 came out at 215.672g, weight 2 came out at 216.135g, and weight 3 came out at 216.362g. Averaging the weights gave 216.056g.

Subsequently, two porcelain crucibles were used, weighed, and heated for about 10 minutes and then placed into a desiccator to cool. The two empty porcelain crucibles were first heated because the heat would vaporize any impurities that were originally on the crucible. The first crucible weighed 11.9047 g and the second crucible weighed 12.3735 g. Once the mass of the two crucibles

XIV. Record your observations of the dried, cooled copper metal and weigh the recovered copper.

3) Repeat the drying process just to be sure that the copper is completely dry, and again determine the mass of the copper and the beaker.

The lab performed required the use of quantitative and analytical analysis along with limiting reagent analysis. The reaction of Copper (II) Sulfate, CuSO4, mass of 7.0015g with 2.0095g Fe or iron powder produced a solid precipitate of copper while the solution remained the blue color. Through this the appropriate reaction had to be determined out of the two possibilities. Through the use of a vacuum filtration system the mass of Cu was found to be 2.1726g which meant that through limiting reagent analysis Fe was determined to be the limiting reagent and the chemical reaction was determined to be as following:-

Weigh out the necessary grams of Copper Sulfate Pentahydrate. The 40-degree group weighed out 40 grams. (See Figure 1)

Before the lab began, stoichiometry was used to predict the net weight of the solids for each reaction. For each trial, the crucible was weighed to calculate the true weight of the NaHCO3 sample before and after it decomposes. A 2g sample of NaHCO3 was weighed out in the crucible. Using a Bunsen burner, the sample of NaHCO3 was heated past 200°C for 4 minutes to allow a thermal decomposition reaction to occur. The sample was taken out of the heat and its weight was recorded to measure the weight of the new solid. The sample was put back into the heat for an additional 4 minutes and weighed again until there was no significant change in the weight to ensure that the reaction had taken place. After washing out the crucible to remove the possibility of a different reaction with the solid and to obtain