Project 6, Session 1 Pre-Lab Worksheet Your TA’s name: Dr. Sakamoto Your name: Andrew Fargalla Lab section: 5E Your email: andrewfargalla@email.arizona.edu GRADE ____ /10 p All work must be well-written and organized. If your penmanship is poor, you must type all responses. If you need to organize your thoughts, please use a separate sheet of paper. A major objective of this lab course is to develop skills in scientific communication. Just having the right “answer” is not good enough – you must communicate clearly and succinctly and use terms and concepts correctly. Question 1 (4 p) Task 1 concerns exploring the thermochromic behavior of cobalt isopropanol solutions (CoCl2(iPrOH)2) with methanol (MeOH). You are to prepare CoCl2(iPrOH)2/MeOH …show more content…
For these calculations assume the temperature remains constant at 25 °C. There are four steps here. First the initial concentration of CoCl2(iPrOH)2 needs to be determined. Second, the equilibrium concentration of CoCl2(iPrOH)2 must be found. Third is the calculation of the equilibrium concentration of CoCl2(MeOH)4, then fourth, the ratio [CoCl2(MeOH)4] / [CoCl2(iPrOH)2] at equilibrium. Show all work. Remember to state the equations you are using defining all variables and constants. Then substitute in the values and show the results. Be certain all sig figs and units are correct. You are expected to follow this format in all subsequent lab work without being prompted. The first thing to do is to find the initial concentration (C2) of cobalt isopropanol: C1V1=C2V2 0.0103 * 3 = C2 * 4 C2 = (0.0103M * 3mL)/(4mL) C2 = 0.0077 M Then find the equilibrium concentration (C3) of cobalt isopropanol using Beer’s law: Beer’s Law: A= lC3 C3 = A/l C3 = (0.705)/((319 cm-1M-1)(1 cm)) C3 = 0.0022 M The third step would be calculationg the equilibrium concentration (C4) of CoCl2(MeOH)4: C4 = C2-C3 C4 = 0.0077 M – 0.0022 M C4 = 0.0055
The results have shown us that all four methods of extinguishing fires which we have used have been successful in putting the fires out but some were more efficient than others. Experiment A, with the vinegar, was the most successful substance. The fires in all the rounds of testing were quickly extinguished and there was barely any smoke. All the fires extinguished using Bottle A, were put out in under fifteen seconds with times such as fourteen seconds, thirteen seconds and eleven seconds. After the different rounds of testing, we also noticed that the product was easier to use and therefore put the fire out quicker. Experiment B, with the bicarbonate of soda, extinguished the fire but it took longer than experiment A and was not too efficient. The fires put out by Bottle B were put out between fifteen and
Through this lab, we will be investigating one factor that will affect the equilibrium constant. The chemical reaction to determine the equilibrium constant is;
To work out the amount of copper carbonate to use I will need to use
Allow the crucible to cool. Weigh the crucible, its lid, and the product of the reaction.
?irst solution began with 5 mL of the stock solution and then equal amount of water was added to
I also want to make the solution to 0.05M because of the ratio 2:1, so
The temperature of the hydrochloric acid solution was measured by placing a thermometer in the graduated cylinder and the measurement was recorded on the observations table.
The stirred crude basic reaction mixture was carefully boiled with a hot plate for about 10 minutes. When most of the dye was dissolved, 5 g of NaCl was added. The crude reaction mixture was then cooled in an ice bath. Then a vacuum filter was set up and two washes were performed with 10 ml of cold NaCl solution. The precipitate was kept after. The crude solid dye weigh 0.37 g.
11. The melting points of pure benzoic acid and pure 2-naphthol are 122.5 °C and 123 °C, respectively. Given a pure sample that is known to be either pure benzoic or pure 2-naphthol, describe the procedure you might use to determine the identity of the sample.
Staudt, Maureen, and Michael Stranz, eds. General Chemistry for Engineering and Science II. Mason,Ohio: Cengage Learning, 2012. Print.
During the experiment I will be taking a number of measurements, I will firstly take the initial temperature of the water and initial mass of the alcohol I will then burn the alcohol until an increase in temperature of 20oc has occurred in the water I will then reweigh the alcohol.
0.1003 M of HCl was diluted tenfold to 0.01003 M. 25cm3 of HCl was pipetted to another 250.0cm3 volumetric flask, then deionized water was added to the volumetric flask until the graduation mark.
Although the initial molarities were given on the chemical’s bottle, adjustments need to be made due to dilutions. In the general experiment and the heated and cooled solutions sections, the concentration of t-butyl chloride is 0.1 M molar because it was not diluted. The molarity of sodium hydroxide for these sections is calculated below.
The rate of reaction was compared to find a linear rate versus t correlation. A constant was needed that was not related to the concentration, namely the rate constant k as shown as below:
The aniline hydrochloride was given in the solid form. So, the mass of aniline hydrochloride to prepare 0.1 M of aniline hydrochloride need to be calculated. The only information given was the molar mass of the aniline hydrochloride. The mole of the of the aniline hydrochloride was calculated by using formula,no.of mole=(molarity x volume)/1000. The mole of aniline hydrochloride calculated is 0.01 mol. Then, by using o.of mole=mass/(molar mass) , the mass obtained is 1.296 g. 1.296 g of aniline hydrochloride was put into the 100 ml volumetric flask and distilled water was filled to the calibration mark. To determine the volume of aniline hydrochloride needed to be dissolved to prepare the solution as instructed, the formula of M1V1 = M2V2 . M1 and V1 are the molarity and volume of the concentrated stock solution while M2 and V2 are the molarity and volume of the diluted solution which need to be prepared. For each of the concentration which need to be prepared, the calculated volume of aniline hydrochloride was put into the volumetric flask and distilled water was filled to the calibration