batigol
Giant
- Joined
- Oct 17, 2004
- Messages
- 37
- Gender
- Male
- HSC
- 2005
its like this, i set up a galvanic cell and i varied the width of the copper electrode (5 widths were used) while keeping the other electrode unchanged. the results showed that the voltage output was always a constant no matter how the width of the copper electrode changed.
i was pretty confident coz i tried copper with 3 other electrodes and found the same result. then my teacher came in and said he was pretty sure it was wrong ie. the voltage should increase with increasing widths.
there are 2 possible explanation for the way we each of us thinks. for me i said that since the voltage for 2 particular electrodes (as found in the standard table) gives energy to the electrons, that energy is fixed. increasing width means increasing number of electrons there are. but this doesnt matter coz the same energy will be given to them anyway, so the current should be the same and hence a constant voltage.
my teacher said something along the line of: if the width increases, theres more surface area for the reaction to happen, so there should be more voltage. he also said that it 'doesnt make sense' to vary only the width of one electrode only, so i should have changed the width of both to see the result.
btw, does the concentration of the electrolyte affect the voltage? are electrode potential in the standard table for solutions of 1M only ( i used 0.1M, didnt think of concentration)
so, i think i sound like a chem problem, but this is an actual experiment lol, anyone have any ideas or have done something similar? thank u
i was pretty confident coz i tried copper with 3 other electrodes and found the same result. then my teacher came in and said he was pretty sure it was wrong ie. the voltage should increase with increasing widths.
there are 2 possible explanation for the way we each of us thinks. for me i said that since the voltage for 2 particular electrodes (as found in the standard table) gives energy to the electrons, that energy is fixed. increasing width means increasing number of electrons there are. but this doesnt matter coz the same energy will be given to them anyway, so the current should be the same and hence a constant voltage.
my teacher said something along the line of: if the width increases, theres more surface area for the reaction to happen, so there should be more voltage. he also said that it 'doesnt make sense' to vary only the width of one electrode only, so i should have changed the width of both to see the result.
btw, does the concentration of the electrolyte affect the voltage? are electrode potential in the standard table for solutions of 1M only ( i used 0.1M, didnt think of concentration)
so, i think i sound like a chem problem, but this is an actual experiment lol, anyone have any ideas or have done something similar? thank u