5. Repeat the titration at least two additional times recording your data in the data table. Do not forget torefill the buret with KMNO4, place the voltmeter probe in the beaker, and add water each time.The molecular weight of FeCl, is 126.75 g/mol.Unknown #Data TableTrialmass FeCl, (g)volume KMNO4 (mL)molarity KMNO, (mol/L)2.051820102+97751.994633Q.081513331.64231800456. Write a balanced net ionic equation for the reaction in acidic solution of FeCl; and KMnOs (Fe* isoxidized to Fe* and MnOi is reduced to Mn). Fe + eSe3+MnOy+ 8*+Se7. The moles of MnO4 can be calculated by multiplying the volume of MnO4 required to reach theendpoint multiplied by the molarity of the MnO4 solution.What are the moles of MnOi used in the titration? D, OC 25 8 37 mol8. The moles of FeCl, can be calculated by using the mole ratio from the balanced equation.How many moles of FeCl; were in the unknown? O:013 ol9. The mass of FeCl2 in the sample can be calculated by multiplying the moles of FeCl, by themolecular weight of FeCl2.What is the mass of FeCl; in the sample?10. The mass % of FeCl, in the unknown sample can be calculated by dividing the mass of FeCl, in thesample by the total mass of the unknown sample.What is the % FeCl; in your unkmown sample?11. What is the average % FeCl; in the unknown sample using your best three answers? 7-3: Analysis of a Ferrous Chloride SampleTitrations provide a method of quantitatively measuring the concentration of an unknown solution. This isdone by delivering a titrant of known concentration into an analyte of known volume. (The concentrationof an unknown titrant can also be determined by titration with an analyte of known concentration andvolume.) In oxidation-reduction (redox) titrations, the voltage resulting from the mixture of an oxidantand reductant can be measured as the titration proceeds. The equivalence point of the titration, or thepoint where the analyte has been completely consumed by the titrant, is identified by the point where thevoltage changes rapidly over a small volume of titrant delivered. In this assignment, you will determinethe mass % of an unknown sample of ferrous chloride (FeCl2) by titrating it with a KMNO4 solution ofknown concentration.Start Virtual ChemLab, select Electrochemistry, and then select Analysis of a Ferrous ChlorideSample from the list of assignments. The lab will open in the Titrations laboratory.12. You will have to drag the FeCl, bottle to the front of the lab bench to see the unknown number.Record the FeCl Unknown number in the data table on the following page. Click the Beakers drawerand place a beaker in the spotlight next to the balance. Click on the Balance area to zoom in, open thebottle of unknown FeCl, by clicking on the lid (Remove Lid). Drag the beaker to the balance to placeit on the balance pan and tare the balance. Pick up the Scoop and scoop out some sample by firstdragging the scoop to the mouth of the bottle and then pulling the scoop down the face of the bottle.As the scoop is dragged down the face of the bottle it will pick up different quantities of solid. Selectthe largest sample size and drag the scoop to the beaker on the balance until it snaps in place and thenlet go. Repeat this again so you have approximately 2 g of unknown in the beaker. Record the mass ofthe sample in the data table. Retum to the laboratory.3. Place the beaker on the stir plate. Drag the 50 mL graduated cylinder under the tap in the sink and fillit with distilled water. It will automatically snap back into place when it is full. Drag the full 50 mLgraduated cylinder to the beaker on the stir plate and then pour the water into the beaker. Now placethe voltmeter probe in the beaker and make sure the voltmeter is on.4.The buret will be filled with 0.0815 M KMNO4. Click the Save button in the Buret Zoom Viewwindow so the titration data can be saved. The horizontal position of the orange handle is off for thestopcock. Open the stopcock by pulling down on the orange handle. The vertical position deliverssolution the fastest with three intermediate rates in between. Tum the stopcock to one of the fastestpositions. Observe the titration curve. When the blue line begins to turn up, double-click the stopcockto turn it off. Move the stopcock down one position to add volume drop by drop.There are two methods for determining the volume at the equivalence point: (1) Stop the titrationwhen a color change occurs. Click the Stop button in the Buret Zoom View. A blue data link willappear in the lab book. Click the data link icon to open the Data Viewer window. Scroll down to thelast data entry and record the volume at the equivalence point in the data table. OR (2) Add dropsslowly through the equivalence point until the voltage reaches a maximum and levels off. Click theStop button in the Buret Zoom View. A data link icon will appear in the lab book. Click the data linkicon to open the Data Viewer window. Click the Copy Data button to copy and paste the data into aspreadsheet program. Plot the first derivative of voltage vs. volume. The peak will indicate thevolume at the equivalence point since this is where the voltage is changing the most rapidly as thevolume changes.

Question

Accepted Answer

9.
Molar mass of FeCl2 = 126.751 g/mol
Moles of FeCl2 given = 0.013 mol
Weight of 0.013 mol of FeCl2…