Ok, I'm trying to figure out some questions regarding an electrochemical cell for and orange juice clock involving a magnesium strip and a copper strip in 400ml of orange juice with wireing connecting them to a clock.
So far I have determined that the Mg is what is being oxidized (and is hence the anode) 1)but I'm a little stuck on what is being reduced - I know it can't be the copper because there are no copper ions in the OJ so what else? Water maybe?
oxidized: Mg(s) -> Mg2+(aq) + 2e- whereE0=2.37V (vs. SHE)
reduced: 2H+(aq) + 2e- -> H2(g) ?where E0=0V (vs. SHE)
overall: Mg(s) + 2H+(aq) -> Mg2+(aq) +H2(g) ?
If so, the E0cell would be
E0cell=E0(reduced 1/2 cell) - E0(oxidized 1/2 cell)= (0V)-(2.37)V
2. The pH of the orange juice was measured to be 1.5. What is the measurement electrochemical potential of the organic juice clock electrochemical cell?
3.The clock requires a minimum voltage of 1.5 volts for it to function. Now, if we replace the magnesium electrode with a lead electrode, will the clock still run? How about replacing the electrode with a stainless steel plate?
4.Would the system work if we put Cu2+ ions into the orange juice solution?
5. What would happen if we titrate the acid solution with a strong base while the clock is running? Explain your observation.
Thanks in advance!!!!