The Interdisciplinary Laboratory
Pre-Lab Assignment
#2 for Experiment #2:
Molecular Weight
of Macromolecules
Pre-Lab Assignment
#2 for Experiment #2:
Molecular Weight
of Macromolecules
The following viscometer flow times
with standard deviation uncertainties have been observed for four polyvinyl
alcohol/water solutions. The average flow time with uncertainty for
the solvent water is 63.63 +/- 0.12 sec.
| concentration (g/100mL) | flow time (sec) | +/- uncertainty (sec) |
| 1.024 | 209.23 | 1.12 |
| 0.853 | 177.90 | 3.28 |
| 0.731 | 152.60 | 2.31 |
| 0.512 | 118.53 | 0.95 |
Calculate the inherent viscosity of each solution and the uncertainty in that calculated value. Determine the intrinsic viscosity of polyvinyl alcohol in water.
Submit via e-mail the solutions to
this pre-lab assignment (the inherent viscosity of each solution and each
uncertainty as well as the intrinsic viscosity of the polyvinyl alcohol
in water) to Professor Johnson (Adam_Johnson@hmc.edu)
by 6 p.m. on Monday, September 16 or Monday, October 14. Turn
in any graphs prepared to answer these questions at the beginning of class
on Wednesday, September 18 or Wednesday, October 16).