Electrolytes
There are lots of stopping points in this lab. The only thing that needs to be completed at one time
is the titration. Otherwise, you can do some of the lab here and there as your time permits.
You may not have discussed the ideas of a polar bond, a non-polar bond, or an ionic bond yet in
class. READ THE APPENDIX!! The appendix walks you through determining the types of bonds
present in a compound.
Some help:
soluble ionic cmpds are strong electrolytes
Insoluble ionic cmpds are non-electrolytes
Strong acids and strong bases are strong electrolytes
Weak acids and weak based are weak electrolytes
Non-polar cmpds are non-electrolytes
Polar cmpds can be non-electrolytes or strong electrolytes or weak electrolytes
If it’s not an acid, base, or soluble salt, it’s a NON-electrolyte.
You may use the solutions directly from the jars – do not pour any out. Just remember to clean
your electrodes on the lightbulb before sticking them into another solution. Remember to unplug
your light bulb apparatus before cleaning/wiping down the electrodes lest you get shocked!
A set-up for the glacial acetic acid is already in the hood for you. DO NOT ADD WATER TO
THIS SET-UP!! Simply plug the light bulb in and write down your observations. Use a separate
beaker for the dilution of acetic acid!
When waiting for your light bulb to turn back on during the titration, it needs to be ON. Not
dimly lit. If someone walked into the room you want them to be able to see that a light is on – if
you are wondering if it is on, then it’s not – keep adding!
For each set of reactions – depending on how you think about things, you may have the same
reaction 3 times in a row – you may not. There are several correct ways to answer the problem –
what you do need is an adequate explanation of WHY the light bulb is on. WHAT exactly is in
that solution that is causing the light bulb to be lit. We need to know specifically what is there!
You need to start learning how to read a buret correctly. To what decimal place should you be
reading the buret out to. If you can read to the tenths place, if the water is partway between 0.1
and 0.2 do you think you can take a guess where the water is?
You will producing a lot of toxic barium waste. This is a heavy metal! It CANNOT go down the
drain. Please dispose of in the CORRECT waste receptacle.