In problem 1.c,(i) Will the cell potential be higher, lower, or the same as the cell potential at the “lower elevation” (typo in the test, it should have said high elevation)?
@eeqeqqe I got basically word for word what you got for that long fr. Not too sure about the graph because it seemed to dip a little too much in the beginning (which isn’t normal). Hopefully we both got 10’s on it
Where were the skipped questions???
@CanisMajor I said it would be the same since the oxygen would be the same, but i have absolutely no idea. I guessed to be honest.
Since it said higher elevation on the AP test, I put that the cell potential would be lower. Due to the cathode receiving O2 from the atmosphere, I thought that it would be lower since there would be less O2 in higher elevation. I could be wrong though xD
@CanisMajor Its not a typo because it’s asking for a comparison to the cell potential at the previous, non-mountain top, or lower elevation.
@CanisMajor It wasn’t a typo, they were asking you to compare it to the cell at lower elevation. But I said it would be higher, according to Nernst. With Le Chatelier’s Principle, at lower pressures the O2 side would be favored and if you look at that with the Nernst equation it would lead to an overall higher potential. Not sure about my justification and overall logic though so it might not be right.
Oh shoot, I must have read the question wrong, then. Hopefully my explanation can get me some credit, though.
@purplechimp thats right. for the prob I said cell potential would lower but i have no idea. I used le chatelier’s principle to justify cause the equation is O2 (g) + Zn(s) becomes ZnO(s) which would lead to less ZnO so less reaction…
@nhnct21 I said the exact same thing!!! but like i could’ve sworn it said higher elevation on he real thing
damnit, I got that part wrong too. Still pretty confident I can get a 4 at least since i think i did great on mc.
@nhnct21 I dont think u can use equilibrium to justify your answer because the cell isnt a two way equation and. It can only go in the forward direction (which is spontaneous) until deltaG is 0 and the reaction completely stops. I used the same logic as Mochis1
So it is lower, then? That’s what I thought.
@pillowspillows: And okay, I’m glad someone else used the same logic as me to answer the question. I believe we’ll get credit for stating that as an explanation.
Too many stupid mistakes
BTW for the half equivalence point pH for the third prob i got roughly 9ish. im pretty sure at that point pH should equal pkb not pka cause its basic at first
@pillowspillows Yeah, not sure if Equilibrium is the right justification, but I think it still has to do with Nernst? Because Nernst includes reaction quotient, which I don’t think you need to be in equilibrium for.
Now that I think about it, I think it is lower. But I think it’s because the partial pressure of O2 is lower, leading to a lower energy because of Nernst.
For question 5B, did you guys say that you had to increase the concentration of the bleach in order to slow down the absorbance of the reaction? This was one of the questions that I was a little bit skeptical of, because I felt like the other two factors wouldn’t really affect the solution.
Will collegeboard ever post form C lol?
@CanisMajor actually no, if you read the question carefully enough, you wouldve seen that it said compare cell potential to that of the lower elevation. And the cell potential would have decreased.
@Mochis1 actually, you had to increase concentration of food coloring. More reactant molecules to react with=slower rate