If you know the anode and cathode already you can get the reaction from that. At the anode you have
Pb ==> Pb^+ + 2e
At the cathode you have
Cl2 + 2e ==> 2Cl^-
Add the two half equations for the cell reaction. You can add the phases.
This is the question I am having trouble with:
A voltaic cell consists of a strip of lead metal in a solution of Pb(NO3)2 in one beaker, and in the other beaker a platinum electrode is immersed in a NaCl solution, with Cl2 gas bubbled around the electrode. A salt bridge connects the two beakers.
I have already figured out that the
--anode is: Pb
--cathode is: Pt
--and that the Pb electrode loses mass as the cell reaction proceeds.
I am having trouble writing "overall cell reaction"
(c) Write the equation for the overall cell reaction. (Use the lowest possible coefficients. Include states-of-matter under SATP conditions in your answer.)
and
(d) What is the emf generated by the cell under standard conditions?
But I realize that I first need to get the correct reaction before I can do part D. If you can help me out that would be much appreciated! Thank You!!
6 answers
Hi Dr. Bob222
Thank you so much for replying! I actually have already tried this equation...
Pb(s) + Cl2(g) --> Pb^2+(aq) 2Cl^-(aq)
and it said it was wrong
So that is why I am confused. Because I was initially solving it the way you had written the half reactions and then joining it together.
Thank you so much for replying! I actually have already tried this equation...
Pb(s) + Cl2(g) --> Pb^2+(aq) 2Cl^-(aq)
and it said it was wrong
So that is why I am confused. Because I was initially solving it the way you had written the half reactions and then joining it together.
I don't know. I don't think it can be PbCl2 forming since the two beakers are connected only with a salt bridge. The cathode surely must be the Cl2 since the Pt is an inert electrode and no conditions are given for the H2O there (that is I don' think we would worry about the H2O reacting). That is the 2H2O + O2 + 4e --> 4OH^-
If you submitted the answer exactly as you posted it to me there is a + sign missing in the products and that could acount for the database saying it was wrong; however, I'm sure that's just a typo.
If that error message persists, I don't know where they are going. Sorry about that.
If you submitted the answer exactly as you posted it to me there is a + sign missing in the products and that could acount for the database saying it was wrong; however, I'm sure that's just a typo.
If that error message persists, I don't know where they are going. Sorry about that.
It turns out I had entered it in wrong! Thank you so much for your help! I really appreciate it!
whew! I'm glad I didn't goof.
You typed the anwser in mixed around. It should be Cl2+Pb--->[Pb}2+(aq)+2[Cl]-
1 answer