Description In this experiment, the non-volatile solid solute is Biphenyl and Solvent is cyclohexane. You have to confirm the molar mass of the solute, using the colligative property of depression of freezing point. Data Collection and Data Analysis: Print out report sheet to conduct data analysis. The experiment has been conducted for you and you are given the data and example graphs. There are 3 Runs: Run 1 - pure solvent cyclohexane Run 2 - cyclohexane with 0.2198g of Biphenyl solute Run 3 - cyclohexane with 0.2033g Biphenyl solute The data sets and the example graphs can be seen in the excel sheet below. You will be adding your graphs to this file. Molar Mass Data Set Excel sheet Keep the Molar mass Data set excel sheet open in front of you. Breakdown of excel sheet: Sheet 1 is an example for data set and has graphs for both run 1 in blue (pure solvent cyclohexane) and run 2 in red (of solution -cyclohexane with 0.2198g Biphenyl - You can see the depression in freezing point in solution compared to that of pure solvent. Sheet 2 has the graph for run 1 only Sheet 3 has graph for run 2 , and also shows the lines of extrapolation used to find the freezing points Sheet 4 - has the data set for the students. It has Run 1 (same as sheet 1 and 2) as well as run 3 (Cyclohexane with 0.2033g Biphenyl - Note that Run 3 has different amount of solute than in Run 2. What you are expected to do: Create Sheet 4. Plot the graph of Run 1 and Run 3 on Sheet 4 using Sheet 1 as an example. Both graphs should be on the same scale. Create sheet 5. Using the same scale as in previous graphs, plot a graph for Run 3 only. Pay attention to how Run 2's plot was constructed for the best fit lines to be drawn. Watch the video below. Alternative to sheet 5 and extrapolating on excel - you are welcome to print out the graph from sheet 4 that was plotted with run 1 and 3, and draw the extrapolated line using ruler and pencil Complete the report sheet using the data of the freezing point temperature of Run 1 and Run 3 - under the data from extrapolation of graph. Use the data to complete the analysis to find the molar mass of the solid. YOU MUST SHOW COMPLETE CALCULATIONS, EQUATIONS AND CONVERSION FACTORS Complete postlab question 1 Scan the report sheet, the graphs from sheet 4 and name them appropriately. Your Lab 4 Report should have purpose, well labeled graphs, Report sheet showing all data and calculations and Result.
Description To access your lab, please follow these instructions-- *if you have already done steps 1-10, simply log in to view your course and participate in lab activities: Please go to: https://oli.cmu.edu/jcourse/webui/register/student.do This will bring you to the “Course Key Students” page. Enter the Course Key “mangan-f20” in the box and click “register.” Create an account by filling in the information (be sure to use an account ID and password you will remember and make a note of it for future logins). Click “I’m not a robot” and “Sign Up.” Confirm your account by clicking on “confirm account.” Read the consent form, then agree by choosing “I agree” and “submit.” Click on “Register” for the Chemistry Virtual Lab Activities with Instructor Manganiello. Click on “Enter course” next to the red arrow to begin the lab. Find the lab required for the assignment and begin work. Should you experience issues, please contact the PSC at 1-866-693-2211 and let them know you need assistance with labs in the CHM1100 course. Under UNIT 1: PowerAde complete the following 3 Modules: Module 1: Introducing PowerAde & Concentration Module 2: Sugar in PowerAde Module 3: A Closer Look: What else is in PowerAde? A total of +15 (or more) correct screenshots will be required (where you enter your answer and they tell you that you are correct). Screenshots should be of the entire webpage, including your name and the page number. If a page must be captured in multiple screenshots, label the images as part 1, part 2, etc. Purpose of Experiment: To modify the concentration of liquids. All of the instructions for this lab are located within ChemCollective. You will step through this lab completing different tasks on different pages. At the end of each task, you will see a "Correct" or "Incorrect" screen. You are able to try again if you see an "Incorrect" screen. Be sure to take a screenshot of each "Correct" screen Submit a zip file of all screenshots for this lab activity. For assistance taking a screenshot, refer to the following guide. For assistance zipping files together, refer to the following guide.
Description Watch the videos for this lab, writing down the data shown. For Part A: Density of pre- and post- 1982 pennies, Trial 1 for each set of pennies is shown in the first video [+], and Trial 2 for each set us shown in the second video [+]. Watch each video and record the data into your data table. Then, enter the data into the questions in this assessment. This will give you feedback on the accuracy of your measurements. For Part B: Density of an Unknown Liquid, watch the third video [+], and record data into Data Table B. Instead of Trial 2, we will calculate the density of a 50/50 mixture of the Unknown liquid with water. You can cross out "Trial 2" and write: Mixture. Then record the data in the same data table. We will NOT calculate an average of these values, since they are different liquids. Part A Trial 1: Density of Pennies Trial 1 for pre- and post-1982 pennies [+] Part A Trial 2: Density of Pennies Trial 2 for pre- and post-1982 pennies [+] Part B: Density of an Unknown Liquid, and a 50/50 mixture of Unknown with water. [+] After recording data from the videos into your data table, enter the following values in the table below: Pre-1981 Pennies Post-1983 Pennies Trial 1 Trial 2 Trial 1 Trial 2 Total Mass of pennies g g g g Volume of water before pennies added (Vinitial) mL mL mL mL Volume of water after pennies added (Vfinal) mL mL mL mL After recording data from the videos into your data table, enter the following values in the table below: Unknown Liquid Mixture Mass of empty graduated cylinder g Mass of graduated cylinder with 10.0 mL liquid g g For Part C, enter the following values in your data table and use these values to complete the calculations for Part C, below. Mass of dry, empty 125-mL flask with stopper 95.439 g Mass of 125-mL flask with CO2 and stopper 95.519 g Actual volume for gas inside the flask 149.8 mL First, calculate the mass of air inside the empty flask. This air gets pushed out when the dry ice sublimes into CO2(g). When you weigh an “empty” flask, it is not really empty; the flask is filled with air. The mass of this air is generally insignificant when compared to the masses of solids and liquids, but it is significant compared to the mass of other gases, like CO2. When the CO2 sublimates, it displaces the air. To calculate the correct mass for CO2, the mass of the air must be subtracted from the mass of the “empty flask”. Use the measured volume of the flask (above) and the density of air (1.2 g/L) to calculate mass. Note the units! Mass of air in flask: g air Calculate the mass of flask if it were truly empty using the equation below:masstruly empty flask = massempty flask — massair in flask = g truly empty flask Calculate the mass of CO2 in the flask using the equation below:massCO2 = massflask with CO2 — masstruly empty flask = g CO2 Finally, calculate the density (in g/L) of CO2 gas (note units!): Density of CO2 gas: g/L CO2
Description 1. How does the attraction the nucleus exerts on electrons in an atom change as the row number increases: 2. Predict the Z number of the smallest element in row 5. 3. Which of the following species is smaller: Cs or Cs+1? Is your answer consistent with your answer to question 1? 4. What simple ion is formed from the element Z = 39? 5. On the basis of electron configurations, predict the formula of the Type I ionic compound formed from the elements Z = 49 and Z = 51. 6. What is(are) the noble gas(es) that has(have) the same electron configuration as each of the ions in the compound formed from Z = 38 and Z = 34? 7. Why is the following electron designation not possible: 18Ar4s2 3dxy 2 3dxz 1 4px2 1 . 8. Draw the Lewis structure for the compound formed from elements Z = 32 and Z = 16. 9. Draw the Lewis structure for the following ion: BF4 -1 . Using VSEPR theory, what is its geometry and electronic structure? 10. Using your Lewis structure for the BF4 -1 , calculate the formal charge on each atom. 11. Draw the Lewis structure for the SeO3 -2 ion, then using VSEPR theory, what is its geometry and electronic structure? 11. Using VSEPR theory, predict the geometry and electronic structure for AlH3 and AsH3. 12. Draw the Lewis structure for the HTeO4 -1 ion, and calculate the formal charge on each atom. 13. How might the valence electrons be arranged in PO3 -3 ion assuming that P can have an expanded octet. Predict its geometry and electronic structure using VSEPR theory. 14. Calculate the formal charges on each of the atoms comprising the hydrogen silicate ion (HSiO3 -1 ). What is its VSEPR geometry and electronic structure? 15. Predict a possible Lewis structure(s) for N2O3. 16. Use VSEPR theory, explain why the bond angle between the fluorine atoms in OF2 is not 180o . 17. Using VSEPR theory, predict the molecular geometry and electronic structures of SnF4 and SeF2. 18. Using the symbol for the previous noble gas to indicate core electrons, write the electron configuration for Z = 46. 19. Draw at least 2 Lewis structures for C3H4F2. 20. Why is the spdf notation for Cr written as: 18Ar4s2 3dxy 2 3dxz 1 3dyz 1 3dx2-y2 0 3dz2 0 , incorrect?
Description In this lab we will determine the molar mass of zinc and aluminum. You need to follow the instructions from the first pdf that is attached. watch this video for help and do the calculations with the 2nd pdf attached. NO PRE LAB, NO Discussion ONLY CALCULATIONS, RESULTS TABLE AND THE QUESTIONS IT ASKS YOU (ATTACHMEMT 3) USE STUDENT NUMBER 27 WHEN YOU GET THE NUMBERS FOR CALCULATION. (2ND PDF)
Description I attempted to complete a lab and I have no idea what I'm doing. I will attach a blank lab. Once matched I can provide additional information. I would need help fixing and thoroughly writing out how problem was solved on this Lab as I've already semi attempted it but had no idea what I was really doing.
Description Chemical Equations Instructions: Write the word equations for the chemical equations below and determine the type of reaction (synthesis/combination, decomposition, single-displacement, double-displacement, or combustion).
