Chemistry FR

<p>so, what was the right answer on the colors question? clear to purple, or were other colors involved???</p>

<p>for the electrochem question, i had clockwise for the electron movement and a negative value for delta G.</p>

<p>:(
I got all the difficult questions right and missed the geometry for SO2
why wouldn't it make sense that S would have two single bonds with O?</p>

<p>There wouldn't be enough electrons to give one of the atoms an octet.</p>

<p>crud... I got the color of the solution wrong, I thought it turned pink since that's what happened in our lab (must've been an altered version that was on the FR).</p>

<p>Yes, SO2 displays resonance.
Yes, I used Henderson-Hasselbach, and got pH of 3.35 or something.</p>

<p>I could never get VSEPR, so I bombed that question asking for the geometry... what was it BTW? I guessed T-shaped...</p>

<p>BTW, for the middle rxn, I got H+ + CaCO3 --> Ca2+ + H2O + CO2.</p>

<p>It was trigonal planar?</p>

<p>IF3 is T-Shaped. 3 Bonding Pairs and 2 nonbonding pairs of electrons, falls under the "Trigonal Bipyramidal" Family.</p>

<p>SO2 has resonance. (I put because of the coordinate covalent bond, so i missed that)</p>

<p>For Electrolysis, delta G MUST be positive and the voltage negative.</p>

<p>I screwed up, but hopefully I can salvage a 4.</p>

<p>for the electrolysis problem, how is E negative?</p>

<p>Re: IF3 and geometry: Oh thank goodness! </p>

<p>E is negative because it's an electrolytic cell, not an electrochemical cell. Thus the reaction is nonspontaneous, and E<0, G>0.</p>

<p>the good thing about electrolysis questions is that you can easily fix your mistakes if you thought otherwise.</p>

<p>the hard part is finding the word "electrolysis", reading it over 50 times, and then realize too much training conditioned you for failure.</p>

<p>at least that's what happened to me ^^. I think I missed maybe 20 pts on FR total. #5 brutally raped me.</p>

<p>How many points total for FR?</p>

<p>Would the answer "trigonal bipyramidal" be acceptable then?</p>

<p>Oh, and I think I forgot the +2 on the Calcium in the limestone reaction...and I think the reactions were some of the few pts that I got...</p>

<p>so... anyone's answer line start after 6e? so there wasn't 6f or 6g? or heard your friends say anything about not seeing the last two questions?? thanks</p>

<p>on num 2, I assumed that delta H was kJ/mol reaction. not per mole NF3.
Is that ok?
And on the electrochem problem, was the direction clock-wise?
I missed part b of Num 2, part c of num 5, part b and c of Num 6.</p>

<p>Do I have a shot at a 5, considering I got at least 50 points on the MC section.</p>

<p>Is there like a formula you can use to see what your composite score would be? I know someone gave me one for AP Lang (I think it was piccolojunior) so there must also be one for Chemistry.</p>

<p>it seems that for one of the questions, many people agree the answer to be</p>

<p>iii)5(55.85)MV/g</p>

<p>That's for the mass percent where it asks you to write it as an expression with M and V. But don't you have to multiply by 100, since its a percent, and not a decimal ratio?</p>

<p>For the question where it asks you to calculate the F-F bond energy, I got 141. However, I wrote at the top of the page, incorrectly, that it was energy of products- energy of reactants. I got the right answer, though, so do I get full credit?</p>

<p>SAT: I wrote 5(55.85)MV/g x 100, because no x100 gives a decimal...you want mass PERCENT. So I believe youd need a x100 somewhere.</p>

<p>I rounded everything to 3 SigFigs, that should be okay for just about every answer right? Considering they give credit for any answer that is + or - 1 digit.</p>

<p>Also, do you guys remember getting 301 for anything?</p>

<p>for the electrochem question .. the answer is that G is positive and E is negative .. but i got the answer other way around .. my teacher told us that graders do not take off points for next parts of FR question if they already took off for the mistake on the first one .. do you think it is true for the electro question?? cuz i thought copper was getting oxidized .. i messed up the entire problem .. did it in correct method but just opposite ..
what do you guys think? i get the entire problem wrong ??</p>