Calorimetry

ABSTARCT In this experiment I have compared three different methods of determining the amount (percentage) of ethanol present in an aqueous sample. I tested three different samples containing different percentage amounts of ethanol in them; Listerine, Terra Fresca Wine and the last is a mixture of ethanol and water that was made by me. The three different methods compared are the redox titration method which involves the oxidation of ethanol to ethanoic acid and then titrating the residue with…

5. Proposed Research Questions and Tasks Four proposed research tasks will direct to fabrication conditions (Task 1), fabrication thermal analysis (Task 2), fabricated parts performance (Task 3), microstructure control methodology (Task 4), respectively. These tasks are designed to answer the questions and solve the problems in the results of preliminary experiments and observations from reported investigations. 5.1. Task 1. Investigating feasible formation conditions and effects of laser power…

1. 6 cleaned and dried conical flasks were collected and safely transported to the experimental table. 2. A black marker was used to mark a black cross on a white sheet of paper. This was to help with measuring the time (dependent variable). 3. A thermometer was placed on the table to measure the room temperature. 4. 0.15mol/L sodium thiosulphate solution (Na2S2O3) and 3mol/L hydrochloric acid (HCL) were poured into two separate 50 ml beakers, and the two beakers were transported to the…

The values calculated through experimentally extrapolated values compare to the the expected theoretical values of these heats with a degree of error. In most cases the values found through experiment were higher than the expected value by one or two kilojoules. This discrepancy causes a 2-5% error in the values calculated. The causes of this degree of error could be sources of errors due to the equipment and set up of the experiment. The experiment is not a perfectly isolated system which could…

In this experiment I will prepare a pure sample of an element (copper) by making a copper solution and then plating it out onto a more active metal. HYPOTHESIS: Because Copper is a more active metal than Iron, I believe the copper solution will plate onto the iron nail. PURPOSE: The purpose of this experiment is to observe reactions between metals depending on which one is more active and observe how to clean pennies, while making a copper solution. RAW MATERIALS: Two plastic cups Clover…

The purpose of this experiment was to calculate the percent yield of copper after conducting series of chemical reactions. To study the % yield of copper in the copper cycle, the initial mass and final mass of copper was measured. The chemical reactions involved in the copper cycle are dissolution, precipitation, dehydration, and oxidation/reduction. First, copper was reacted with in a beaker to form (aq) and . The purpose of the dissolution reaction is to convert the copper into solutes in…

In order to safely dispose of a solution with a pH of 12, the solution needs to be diluted with an acid to neutralize the basic solution. The pH range should be between 5 to 8 to be ready for disposal. 2. A graduated cylinder, Erlenmeyer flask, and beaker were used to measure a 60-mL volume. Which of these devices seems to be the most accurate for measuring a 60-mL volume? Be sure to explain what the term ‘accurate’ means. How did you determine this during lab? State some reasons why this…

The purpose of this experiment was to determine the identity of nine solutions using the results of reacting pairs of solutions in an organized systematic manner. Known solutions were used on the first day. The second day, the solutions were placed in code-labeled bottles. The reactions from the previous day were then used to help identify which solutions were which, by closely monitoring which unknown solutions mixed with other unknowns and how they reacted, such as: color changes,…

Introduction Four reactions were done using coffee cup calorimetry for each. Two Styrofoam cups were stacked together for each reaction performed, with a piece of cardboard used as lid with a hole for the thermometer. The beginning and final temperatures were taken for all reactions and solvents used. The end result and point of the experiment is to find what ΔH. Also this is a constant pressure calorimetry experiment. The goal of each of the reactions is to get ΔHrxn which is represented in…

Heat water in a pan or beaker until it is boiling vigorously. While the water is boiling, measure the mass of your metal object, marking off your answer to one more decimal place than what the scale marks off. Once the water is boiling, drop the metal into the water, leaving it in for about five minutes to allow it to reach the temperature of the water (100.0 °C) Place one Styrofoam cup into the other. This will be your calorimeter. Measure the mass of the calorimeter. Fill about ¾ full with…