Muzz1969
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Reaction time/time to completion
Is the reaction time calculations different when we use and electrolytic cell. Do we need to work out a specific voltage for each type of reaction or
can we set any voltage? Do these varying parameters effect yield?
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gdflp
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Voltage has nothing to do with calculating the length of time an electrolytic cell has to run for. Current is a measure of Charge/Time and this will
dictate how long you need to run your cell for. Firstly calculate how many "mols" of electrons your reaction needs to go to completion. Then use
Faradays constant to convert mols to coulombs. 1 amp = 1 coulomb/second, so divide the total number of coulombs needed by the current and divide by
3600 to find the total number of hours neede to complete the reaction, assuming 100% efficiency. Voltage will determine if a reaction will occur, but
higher voltages will not increase reaction rate.
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Muzz1969
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Does the surface area of the carbon rods have an affect on the reaction time, ie more area less time ?
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Oscilllator
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No. The reaction time depends solely on the current (and efficiency), as this is a measure of the number of electrons per second passing through the
cell. Since a certain number of electrons are needed to complete the reaction, one divides the total number of electrons needed by the rate the
electrons are flowing at to obtain the time for the reaction to be completed.
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gdflp
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Theoretically, no. However, it depends on the cell design, if you have no way of stirring it, then a large surface area will slightly lower reaction
time as the rate is partially based on diffusion.
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Muzz1969
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Thanks guys, I think I'm going to try and set up an experiemnt to oxidize ethanol with a cell I have built from a test tube and some pencil graphite
I'll put up my calculations and would be grateful for any corrections , I'm trying to my skill set ready for uni at the end of February
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