Membrane Permeability
Place a “cell” containing HCl into a water bath and over time you will see that the pH of the water bath has decreased. This indicates that the membrane is permeable to H + ions..
Lab Summary
Explore the permeability of a cell-like membrane to hydrogen and hydroxide ions.
Downloads
- Download Free Lab, (PDF, 656 KB) (590 KB, .pdf)
Method
Use a pH Sensor to measure the pH outside of a model cell to determine its permeability to hydroxide and hydrogen ions.
Here's What You Need
U.S. Educator prices shown.
Probeware
PASPORT pH Sensor (PS-2102) - $79
Has a wide measurement range of 0 to 14 pH. Has a resolution of 0.01 pH. For use with PASPORT Interfaces.
Xplorer GLX (PS-2002) - $349
The Xplorer GLX is a data collection, graphing, and analysis tool designed for science students and educators.
Other Products
Buret Clamp (SE-9446) - $12
The V-shaped, plastic-coated jaws will gently hold a buret and lock at any angle.
Graduated Cylinder, 50 ml (12 Pack) (SE-7289) - $119
This 50 ml Graduated Cylinder is borosillicate student-grade glassware for use in the physics lab. Package of 12.
Other Materials
- Beaker, 250 mL
- Binder clip
- Magnetic Stirrer and Stir Bar
- Wash bottle
- Dialysis tubing, 15 cm, 2
- Hydrochloric Acid. 1 molar, 15 mL
- Sodium Hydroxide, 1 molar, 15 mL
- Water, Distilled, 1 L
