Would you agree regarding the FRQs? This is not a big deal I would hope and it looks like most things came down to basically single concept plug and chug problems except for the couple of conceptual items. I think you’ll have to have “higher energy” in there somewhere. That said, I agree with Matt’s point that buffers are one of the harder topics. The prompt says “no reaction is OBSERVED to occur.” That does not mean that there are no collisions with sufficient energy, just that there are too few to produce an observable reaction. That doesn’t look bad at all. There are also a bunch of unofficial resources for AP Chemistry practice questions on various online learning platforms and independent sites. I did that too and did hours ^ -1. 2017 AP ® CHEMISTRY FREE-RESPONSE QUESTIONS © 2017 The College Board. I agree. And that’s on the assumption those are what I got for the other Free responses and MC (though I’m sure there is no way I got less than 53 on the MC). There are decades of problems based entirely around buffers. If they did intend for a calculation then I feel they should have asked for the actual pH to lead students down the calculation path. Byron. Also, with the reaction being exothermic, heat is product so as temperature got higher, it would become even more reactants favored based off LeChateliers principle? The first section has 60 multiple-choice questions. Incidentally, Adrian, my students are grateful to you for the tip about reviewing titrations. In (b) I cannot imagine a calculation of Rf would be required. All I knew was the Henderson Hasselbach sh*t and some other small concepts related to buffers. Also, all the past AP exams since 2013 didn’t have “full” buffer questions so there’s that. Honestly, sig. Burning an alcohol -water mixture must produce less energy than burning pure alcohol, since the water doesn't burn. my apologies, you are correct, my bad-i got it backwards. 50/50 for sure. I said, “On a recently administered new exam, it was 79”. Btw, I wouldn’t be surprised if I got 58+/60 on MC. 64-78 = 4 Much easier than last year, in my opinion. Formal charge is 0 The carbon on the right has THREE bonded pairs, plus one lone pair. Will 103 degrees be accepted for the angle? Shouldn’t the cell potential be 3.10 V? 1 and 2 were easy. Also, if one plans to pursue chemistry or any STEM degree in a research context, it is all about reading and dealing with complex scenarios. 79-100 = 5 I expected buffers to be 1 part to a greater question — not a whole question. See the balanced equation for the reaction. I’m retaking the exam next year if I don’t get a 5. The formal charge is still 0 on all of the atoms involved. Especially a 10 point question (he/she didn’t even have the decency to make it a short answer). It was presented as if its insignificant. AP Exams are regularly updated to align with best practices in college-level learning. That was NOT the 2015 Operational Exam. There goes my 5. You could reason out that at the same temperature both CCl4 and HCl have the same kinetic energy… because CCl4 is in liquid state, the IMF’s were strong enough to cause attraction to other CCl4 molecules and caused the condesation. The carbon on the left has 4 bonded pairs of electrons. Wouldn’t you like to know what they are thinking about the 2017 AP Chemistry Exam? For sure. Only time will tell. This comes from a private research university in Atlanta. Should you find an error PLEASE let me know by commenting on this post below, rather than emailing me or using the contact form me (that way all problems can be addressed in this post), and I will comment/change as necessary. It’s eating me alive knowing I got only 2 points on it. 2/10 Q3 Last year: Almost impossible to do without seeing the MCQ’s, and in the light of the instability of the new exam. The word form person that graded Q1 is that is was NOT accepted. Part (d) is tricky IF it wants something OTHER than capacity. There does seem to be a trend away from calculations overall, so perhaps they were just intending for students to just be able to reason it out instead of to calculate it. I understand what you wrote for that in terms of delta G etc. For 2(e), do you think it will be ok if students calculated several values of ln[CO(NH2)2] vs time and found a consistent slope? My 2017 AP Chemistry Released Exam Draft Answers & Comments appear below. How hard would you say this is compared to the Chemistry Subject test? It’s very difficult to tell. May 4, 2017 | AP, College Board | 128 comments. For #1bi, if we just said the frequency of the collisions increases (without mentioning “with sufficient energy”), would we still get a point? How much time was your class able to spend on acids and bases overall? Anyway, my students struggle a lot with buffers, and as you saw on the Reddit forum, so do a ton of other people. But the buffer one was so dumb. Just hoping the International test looks similar. Maybe. 1. In fact, I would be perfectly happy (and would hope it would get full credit) with a response that explains the increase in rate ONLY in terms of higher energy collisions, and does not mention increased collision frequency. Both this questions where LDFs dominate and acid/base buffers are on the exam every year. Hi Adrian, a quick question regarding 1b(ii), the graph which you sketched crossed the activation energy line, however, it mentioned in the question that no is observed to occur. Your email address will not be published. Is this accurate? I believe both reduction processes should be accounted for. for this one, even if you didn’t know electrochem well, you could reason it out. Just took my AP Calc exam. Josh, I’ll quote Paul C., and his comment below. 3c – I imagine that once the net ionic equation has been written, simply pointing out that when a weak acid and its conjugate (as shown in the equation) are present, the solution is a buffer, would be sufficient without discussing limiting factors. In fact, honestly, there were not many real world context problems here. As for the reading thing, I guess it depends on what you think school is for, and what skills it needs to be delivering. I would not accept that answer to 3d, and don’t expect that it will be accepted. No. If you were to make a prediction of the total score cut offs for %’s, 4’s, 3’s, what would you predict? I know I would. I’m confused by part (c). I still can’t believe I scored a 2/10 on it. no, that’s not accurate.