I'm in kind of a pickle here. I made a galvanic cell of Lead and aluminium for a chemistry internal assessment but unfortunately, it didn't turn out so well and neither me nor my teacher has any clue why. The E0 value of the cell is 1.53v. I got a maximum reading of 0.29v
If you don't have time to read here is what I think the sources of error could be: 1. I used filter paper as a salt bridge and I don't think it was thick enough to allow ions to flow through it. 2. I used around a 1M concentration of KCl to dip the salt bridge in. 3. I suspect either of the metals was not correct but this seems improbable as I got a voltage just not the correct one. 4. The solutions of AlNO3 and PbNO3 were kept in round-bottomed flasks with a glass cork in them for a few days before I decided to do the experiment. 5. I got a negative reading for the voltage which was weird. 6. I got a higher voltage reading only when I touched the aluminium rod to the salt bridge in the solution
I used the following procedure:
- I made 0.01M, 0.1M, 0.25M and 0.5M solutions of aluminium nitrate and a 0.1M solution of lead nitrate (both well dissolved) from lab equipment.
- I poured each of them into separate 50ml beakers. I then placed an aluminium rod (that was 50% submerged) into the AlNO3 beaker and a thin piece of lead (that was well sanded before each reading) that was fully submerged in PbNO3.
- I connected each of the metals to a multimeter via alligator clips
- I then prepared a salt bridge using 5x25cm strips of filter paper which were dipped in a solution of KCL of about 1M concentration. The filter strips were folded and stapled.
- I then placed the salt bridge in both the beakers and conducted the experiments.
I'm not in school right now and I don't have time to conduct the experiment again as the assessment is due very soon.