Calorimetry

Introduction: The goal of this lab was for students to learn how to use a spectrophotometer to find the absorbance of four known copper (II) sulfate solutions, four copper (II) sulfate solutions that were created by dilution, and one unknown copper (II) sulfate solution. The purpose of this experiment was to help students learn how to use the Spec-20, which is a machine that measures the transmittance and absorbance of a solution, learn about the linear relationship between absorbance and…

Abstract The goal of this experiment is to understand the theory behind bomb calorimetry and use it to determine the enthalpy of combustion of naphthalene. First, the bomb calorimeter was standardized using benzoic acid and the average heat capacity of the bomb calorimeter was calculated to be 10.60.3205 kJ/K. From that, the average m, and f were found to be -526615.66kJ/mol, with a percent difference of 3.31%, -52600.0015kJ/mol with a percent difference of 1.99%, and -185.50.0013kJ/mol with a…

Brooke Beams February 2, 2012 Experiment 1 Determination of the Components of a “Mixed Drink” INTRODUCTION. For this experiment standard solutions of Kool-Aid flavors will be prepared to measure the absorbance at lambda max and plot the results against the concentration of solution to generate a standard curve. Then it must be determined the amount of each flavor in a sample of the unknown by comparison to your standard curves. The ingredient in each flavor of the Kool-Aid that…

Determining the Percentage Yield of a Chemical Reaction Question: What is the percentage yield of the reaction of sodium carbonate and calcium chloride dihydrate (the dihydrate must be included with the molar mass calculation)? Predictions: Predict the mass of sodium carbonate and calcium chloride dihydrate that will be required to produce 1.90 grams of calcium carbonate: Therefore, the predicted mass of sodium carbonate is 2.0 grams and the predicted mass of…

Prepare a chart for recording any observations as you test for the presence of cations in the solution. Set up and label 10 test tubes #1- #10 and place them in order in a test-tube rack. Wash and rinse all of glassware with distilled water. Prepare a hot-water bath in a 250 mL beaker by filling it up to 150 ml and bringing it to a boil. Obtain 2 ml of the solution you want to test and pour it into test tube 1. To test the solution for Pb2+ and Ag+ ions, add 8 drops of 6 M HCl solution to…

A graduated cylinder was used to measure 200mL of distilled water into an Erlenmeyer flask and then 40mL of 0.6 M NaOH was added to the distilled water in the flask. The flask was then plugged with a rubber stopper and shook in order to mix the solution. A buret was then washed, rinsed with distilled water, and then 5 mL of the NaOH diluted solution. After the cleansing of the buret, it was then filled up with the NaOH diluted solution. The dilution of the solution was calculated to find the…

Summary: This lab involves three separate experiments. Before you conduct any of them, however, you should put on goggles and aprons, as well as gloves. For the first part, place the FeCl3 solution into the watch glass, and add a few drops of KSCN. Record any changes you might see. Then, ask Dr. Karraker to add a KSCN crystal to the watch glass, and again record any changes. Add drops of Na3PO3 and record any changes, then add FeCl3 and record those changes too. After you are done, dump the…

In the volume lab, we found that the large graduated cylinder was the most accurate because it had less percent error when measuring the density of water over all of the other measuring tools.In this lab, we measured water from pipettes including volumetric and graduated pipettes, graduated cylinders, erlenmeyer flasks, and beakers to figure out the mass and density. These measurements were then used to calculate the percent error. We completed these measurements by measuring the volume of the…

Apparatus • 1x hot plate • 1x electronic scales • 4x 100mL beaker • 4x glass stirring rod • 4x thermometer • 1x chemical spatula • 500mL of deionised water • 500g of sugar (sucrose – C12H22O11) • 100g of salt (NaCl) • 100g of copper sulphate pentahydrate (CuSO4•5H2O) Method 1. Fill a 100mL beaker with 50mL of water and then weigh it using electron scales and take note of the mass. Place the beaker on the hot plate, but don’t turn the hot plate on. 2. Place a thermometer in the beaker of water…

B. Buffers. 1. Two solutions, A. being 1.0 x HCl, and B. being 0.10 M will be given, as well as buffer solution 1 M NaOH. 2. Have 25 mL of solution A. and B. in two separate beakers. 3. Check the pH of both solutions without any NaOH first. Then begin checking pH after 1 drop, then after 10 drops, and lastly 25 drops. After each set of drops be sure to mix solutions. 4. Compare both sets of pH to determine which had an easier time resisting change. C. Titration curves. 1. Insert NaOH into…