The relative viscosity of 2,2,4-trimethylpentane can be measured using a stopwatch, and compared to other liquids.
To measure relative viscosity an experiment is shown where the rate of flow of six different liquids through a Mohr pipet is determined. The experiment is set up so that the times at which the liquid reaches the 0 mL and 3 mL marks on the pipet may be observed. The rate of flow depends on the size and shape of the molecules as well as on the types of intermolecular forces involved.
With the associated videos, it is possible to determine the relative viscosities of the water, hexane, octane, 2,2,4-trimethylpentane (isooctane) and 1-pentanol from measurements of the times when the meniscus passes the zero and 3 mL marks on the pipet. Viscosity is inversely proportional to the elapsed time.
- Design and Demonstration
- Frederick Mattes Hastings College, Hastings, NE 68902
- Video
- Jerrold J. Jacobsen University of Wisconsin - Madison, Madison, WI 53706
- Text
- Frederick Mattes Hastings College, Hastings, NE 68902
- Kelly Houston Jetzer University of Wisconsin - Madison, Madison, WI 53706
- David Phillips Wabash College, Crawfordsville, IN 47933
- Nancy S. Gettys University of Wisconsin - Madison, Madison, WI 53706