Final Lab Report Sample

Before the experiment, several pieces of glass were put into an oven to dry, and the heat from the

(.1063 KIO31) (1 mol KIO214 g) x 6 mol S2O41 mol KIO= .00298.04150= .259 M

3. Carefully felt the sides of the test tube and observed the resulted chemical reaction for about 30 seconds.

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 Copper Chloride displayed and used to complete this lab had led us to the following observations;

The objective of this lab was to use prior knowledge about the Law of Conservation of Matter and of different types of chemical reactions in order to evaluate if aluminum disappears during the reaction and copper appears. The reaction that occurred between Copper (II) Chloride and aluminum was a single replacement reaction. Clear signs that a chemical reaction took place include heat release/temperature change, color change, and formation of a precipitate. When a single element, in this instance aluminum, replaces another element in a compound, copper, a single replacement reaction occurs. A basic formula for these reactions is AB + C → AC + B.

between the unknown cation and chlorine (Cl - ) was also formed from the addition of HCl. HCl was

5. Was there any evidence that some of the copper (II) chloride was left in the beaker? Explain.

Using elemental analysis to determine the percent mass composition of each element in a compound is the first step in creating an empirical formula. There are many different types of elemental analysis, but in this experiment gravitational analysis and Beer’s Law are used. Elemental analysis is first used to find the moles of each element, then converted to mass, and then the percent mass of the element in the product is found (2).

Eleven mystery test tubes labeled from K-1 to K-11 contained: 6M H2SO4, 6M NH3, 6M HCl, 6M NaOH, 1M NaCl, 1M Fe(NO3)3, 1M NiSO4, 1M AgNO3, 1M KSCN, 1M Ba(NO3)2, 1M Cu(NO3)2 respectively. The contents of the test tubes were determined by chemical experiments. Solution K-1 contained NiSO4 because when solution K-9, ammonia which was identified by its pungent odor, was added, an inky dark blue color was made. Iron (Fe (NO3)3) was determined to be in test tube K-2. KSCN was found in test tube K-11 since Fe (NO3)3 and KSCN makes a bloody color when mixed together. Flame tests were conducted in which K-8

In the lab it uses the definition equilibrium constant, what is meant when equilibrium constant is referred to, is the ratio of the molar concentrations of the reactants and products for the reaction. But in order for the ratio to be accurate the system must of reached equilibrium and temperature must have stayed constant. The value of Keq obtained from all our experiments was nearly

Finally, we measured the mass of the remaining copper in the test tube. This lead to the discovery that the mass of the copper in relation to our original 1.08 grams of copper oxide was 0.96 grams. From this data, we could find that the measurement of oxygen in our amount of copper oxide was 0.12 grams. With these significant weights, we were then able to convert those results to the amount of moles each element had in contribution to our total quantity of copper oxide. Specifically, we found that there was 0.015 moles of copper in our copper oxide, and 0.0075 moles of oxygen. So, that made the calculated ratio between moles of copper and moles of oxygen to be 2.0, or a 2:1 ratio of copper to oxygen. Thus, the formula of the red copper oxide can be expressed as . The lab worked the way it did primarily because of the chemical characteristics of copper oxide. Since the oxygen could separate from the copper when presented with a heat source, it allowed for the amount of each element in our quantity of copper oxide to be measured and then calculated into a ratio, which determined the formula for the

Firstly, after removed from the Bunsen burner, the crucible was not given time to cool down before being weighed. Weighing a hot crucible can affect the accuracy of measurements by making the crucible appear to weigh heavier, causing the results to be overstated. Secondly, as state in the paragraph above, both samples did not weigh exactly 2g. In trial 1, the sample weighed slightly less than 2g but in trial 2 the sample weighed slightly more than 2g. Consequently, the net weight for the solid in trial 1 was understated and the net weight for the solid in trial 2 was slightly

Then, each group of students received the necessary materials to complete the experiment. When the students received the cups, they labeled cups to distinguish between the salt solution, distilled water, and control group. After weighing the cups and finding the mass of the cucumbers, the students poured 50 ml of water in one cup, 50 ml of salt solution in the other, and left the control cup empty. Then, the students placed the cucumbers into the cups and waited 30 minutes for the results. After the 30 minutes, the students removed the cucumbers from each solution and dried the cucumbers with paper towels. The students then weighed the cucumbers again and recorded their results. Lastly, the students found the difference from the original mass of the cucumbers and recorded their results.

2cm of a solution was tested and added 2 cm of 10% of potassium hydroxide solution and the test tube was shaked.