-Advertisement-
  About AE   About NHM   Contact Us   Terms of Use   Copyright Info   Privacy Policy   Advertising Policies   Site Map
   
Mystery Spot
Activities Collections
Health Headquarters
Resources
Custom Search of AE Site
spacer spacer







LAB 2 - NaCl vs. CsCl

Question: How do different salts compare in their ability to carry an electric current?

Hypothesis:___________________________________________________________________

____________________________________________________________________________________

____________________________________________________________________________________

____________________________________________________________________________________



Test: _____________________________________________________________________________

____________________________________________________________________________________

____________________________________________________________________________________

____________________________________________________________________________________
Materials:
As described in LAB 1 and including CsCl (anhydrous), M.W. = 168.37

Procedure:
As described in LAB 1 with the following modifications -
  1. Because CsCl is prohibitively expensive, ways should be found to conserve this salt. For example, have the students make up solutions of 2.9 gm/50mL or have one group in the class make up one or two beakers of 5.8 gm/100mL for the rest of the class to share.

  2. The currents measured for equal volumes of NaCl and CsCl stock solutions in the electrophoresis chambers, will be quite a bit lower for CsCl than NaCl. This, of course, is the first puzzle the students will confront. However, to ensure that their measurements will be accurate, they should try some larger volumes (e.g., 5mL, 10 mL, 15mL) of CsCl.

Data:
  1. Two data tables, one for each salt.

  2. Students should plot the data for the two salts on one graph.

Analysis/Conclusion:
As in LAB 1. Students should be instructed to attempt an explanation of any differences in behavior between the two salts as exhibited by their graph.


LAB 1     LAB 3     LAB 4     General Instructions


AE Partners Collection Index

Activities Exchange Index

 
Custom Search on the AE Site

 
-Advertisement-