- Yes 5pts Molar Mass Of A Solute Using Freezing Point Depression Are You Completing This Experiment Online Data Collec 1 (19.4 KiB) Viewed 76 times
- Yes 5pts Molar Mass Of A Solute Using Freezing Point Depression Are You Completing This Experiment Online Data Collec 2 (17.78 KiB) Viewed 76 times
- Yes 5pts Molar Mass Of A Solute Using Freezing Point Depression Are You Completing This Experiment Online Data Collec 3 (21.79 KiB) Viewed 76 times
- Yes 5pts Molar Mass Of A Solute Using Freezing Point Depression Are You Completing This Experiment Online Data Collec 4 (16.27 KiB) Viewed 76 times
- Yes 5pts Molar Mass Of A Solute Using Freezing Point Depression Are You Completing This Experiment Online Data Collec 5 (20.67 KiB) Viewed 76 times
- Yes 5pts Molar Mass Of A Solute Using Freezing Point Depression Are You Completing This Experiment Online Data Collec 6 (19.47 KiB) Viewed 76 times
- Yes 5pts Molar Mass Of A Solute Using Freezing Point Depression Are You Completing This Experiment Online Data Collec 7 (31.23 KiB) Viewed 76 times
78.7 776 76.6 756 746 73.7 210 seconds 240 seconds 270 seconds 300 seconds 330 seconds 360 seconds 390 seconds 420 seconds 450 seconds 480 seconds 510 seconds 540 seconds 570 seconds 600 seconds 728 720 713 70.6 200 59.6 69.4 630 seconds 693 660 seconds 693 690 seconds 603 720 seconds
750 seconds 693 780 seconds 69.2 69 2 810 seconds 840 seconds 870 seconds 692 69.2 900 seconds 69 2 Time and Temperature Data: Cooling Curves for Solution with Unknown 1 1.007 Unknown number Weight of unknown used Table 2. Cooling curve for stearic acid with unknown solute Table 2. Cooling curve for stearic acid with unknown solute 2nd Cooling Curve Temperature (°C) O seconds 85.0 30 seconds 83.5 60 seconds 82.1 90 seconds 80.7 120 seconds 79.3
150 seconds 779 76.6 753 740 728 1B0 seconds 210 seconds 240 seconds 270 seconds 300 seconds 330 seconds 360 seconds 390 seconds 420 seconds 717 70.5 69.4 684 675 450 seconds 66.6 4B0 seconds 658 510 seconds 65.1 45 540 seconds 570 seconds 600 seconds 643 630 seconds 64 660 seconds 643
VW VOW Table 3. Freezing point determination Cooling Curve #1 Cooling Curve 2 Final time to include in cooling portion De Choose Choo Choose Slope of cooling portion y-intercept of cooling portion Slope of freezing portion y-intercept of freezing portion Time at which 2 lines intersect (seconds) Calculated freezing point (C) (13pts) Determination of Molar Mass Complete the following calculations to determine the molar mass of the unknown added to stearic acid Table 4. Determination of molar mass
Table 4. Determination of molar mass Result 71.602 Mass of test tube, besker, and stearic acid (C) Mass of test tube and beaker (a) 62625 Mass of stearic acid (6) Unknown number Mass of unknown (0) 1 1.007 Freezing point of stearic acid (calculated above) (°C) Freezing point of solution (onlculated above) (C) Freezing point depression (C) Molulity of unknown in solution ( Moles of unknown in solution (mol) Molar mass of unknown (g/mol)
• 642 642 642 642 690 seconds 720 seconds 750 seconds 780 seconds 810 seconds 840 seconds 870 seconds 900 seconds 642 641 64.1 541 (28pts) Determination of Freezing Points Use the data tables shown above to make two plots of cooling curves using graphing program. Each cooling curve is a plot of temperature (vertical axis) versus time (horizontal axis), and contains a cooling porting (when the liquid is cooling) and a freezing portion (when the liquid is turning to solid). You will need to generate a trendline for each portion of the cooling curve. In order to do this, you will need to identify which points to include in the cooling portion, and which points to include in the freezing portion For each cooling curve, identify the last temperature measurement to include in the cooling portion of the curves. Then generate a trendline each portion and record their slopes and intercepts in the table below Table 3. Freezing point determination Table view List view Table 3. Freezing point determination Cooling Curve 11 Cooling Curve #2