Electrolysis Lab

Hook one end of the copper wire onto the bottom of the sample cup and the other end hook it on the outside of the cup.

Fill half of the Sample cup with distilled water and stir copper (II) sulfate crystals until it dissolved.

Attach the battery cap to the 9V battery.

4- Test these combinations to know which provokes a reaction.

Touch the red wire/test lead to the copper wire in the sample cup, and observe/record any reaction.

Touch the black wire/test lead to the copper wire in the sample cup, and observe/record any reaction.

Attach the paper clip to the red test lead.

Place the paper clip, attached to the red test lead, into the solution and observe/record any reaction. Ensure that only a portion of the paper clip is submerged, not the wire coming from the red test lead (which must be kept out of the solution).

While the paper clip is in the solution (attached to the red lead), touch the wire coming from the black test lead to the copper wire in the cup. Observe closely any reaction or changes you see in the paper clip that is in the solution. You may have to allow it to remain for a few seconds/minutes in order for the reaction to proceed.

Take the paper clip off the red lead, and attach the paper clip to the black test lead.

Place the paper clip (attached to the black lead) into the solution, observe/record any reaction. Keep only the tip of the paper clip in the solution. Do not allow the wire from the test lead to be submerged in the solution.

While the paper clip (attached to the black lead) is in the solution, touch the red lead's wire to the copper wire hanging in the cup for one second.

Remove the paper clip from the solution, and observe/record any changes in the appearance of the paper clip.

While the paper clip that is attached to the red lead is in the solution, touch the black lead (bare wire) to the copper wire. Allow this connection to remain for at least five minutes, and observe any reaction at either end of either wire closely. Observe the paper clip, noting any changes.

Data:

When the red wire touches the copper, the copper will start depositing in the Cu wire.

When the red wire touches the copper, the copper will start dissolving in the solution.

When Paperclip attached to the red wire copper starts depositing on it. With this solution when black wire is attached to the copper wire, the copper wire from wire starts dissolving in solution.

When Paper clip attached to the Black wire, no reaction takes place. When in this condition black wire is attached to the copper strays depositing in the wire and after some time the reaction stops as cu2+ions concentration is decreased.

1.Explain What happen and why each of the combinations either reacted or did not react in Step 4.

2.Why weren't the reactions the same in each case? For some of your answers, consult the Standard Reduction Potential. (Note: The battery was 9V, although you should remember that the easiest pathway is what is followed.)