The Official AP Chemistry Discussion Thread

<p>Ohsacul I LOVE YOU FOR THE AUDIT!!!</p>

<p>Where does (aq) fit on a scale of physical states? I know it goes Solid–>Liquid—>Gas, but where does aq go again??</p>

<p>Does anyone have the answers to the 2004 MC? I can’t seem to find them anywhere</p>

<p>I don’t think it’s a state. It means solute in water.</p>

<p>The 2004 is the exact same as the 2002.</p>

<p>^do you mean the 2002 MC? I dont have the 2004 MC can you send that to me, I thought the most recent one was 2002…</p>

<p>oooo didn’t realize thanks velleity =]</p>

<p>the reason im asking is b/c of this problem from PR, in terms of if the entropy is positive?: NaCl(s) — > Na^+(aq) + Cl^-(aq) so it says in the answers that this is true because aqueous particles are more disorderly than solids. so do aq particles go b/w solids and liquids in terms of relation to entropy???</p>

<p>(aq) is considered a state (dissolved)</p>

<p>Btw whoever wrote the HH equation back there got it wrong. It’s pH = pKa + log [A-]/[HA]</p>

<p>Hey guys, I never seem to be able to get the problems that ask Which of the following equimolar solutions will act as a buffer solution. One possible set of answer choices include
a) H2SO4, Na2SO4 b) NA2S KHS c)H2SO4 H2SO3 d)KOH KCN e)HI KI</p>

<p>a) H2SO4 is a strong acid, so that’s out.
c) first off H2SO4 is strong and second H2SO3 has nothing to do with buffers
d) you have a strong base and conjugate of a weak acid…wrong
e) HI is a strong acid so that’s out</p>

<p>A buffer is composed of a weak acid/base and its salt.</p>

<p>I’m scared beyond belief. I havent done enough review. I did a practice test and got 61% for MC and i did really well on the FRQ. i got 110 and the cutoff for a 5 is 100. im still scared tho. im afraid ill freak out, hyperventilate, not know how to do a question and just make some dumb mistakes. Bleh. X__X</p>

<p>I transferred between semesters and there was overlapping in what I learned. So I ended up going over Kinetics and Equilibrium twice. While my first teacher was anal retentive OCD, my second was really lax, both ended up going in the extremes… so not good for me. lol, especially with stuff I missed.</p>

<p>I hear the equations section is actually the hardest part of the FRQ section.</p>

<p>hey guys I’m back!! haha. Let’s get this party started.</p>

<p>BTW, There is a 2008 audit which I posted on page 24 if people don’t already have/know about it.</p>

<p>Sixth Sense I would of assumed A.) so I dont know how’d they get B</p>

<p>so where does aq fit in b/w s–>l—>g ??</p>

<p>PV=nRT
G= delta H -(Tmultiplied by delta S)
S universe= S surroundings + S system
Molarity= mols/liters
pH = pKa + log [A-]/[HA]</p>

<p>how to do find the order of a reaction from just looking at concentration vs. time graph?
for example, number 63 on 1999 test.
It looks like 2nd order to me since 1/concentration is a straight line…</p>

<p>jamesford, that is what i said. its ([A-]/[HA]) not just log [A-] / [HA].</p>

<p>hey, are the titration questions on the test like strong acid weak base or vice versa or are they just the normal ones. How big of a chance do you think there is for titrations to be on the FRQ?</p>

<p>So, anyone want to explain the differences between Ka, Kb, common ion effect, buffers, and titrations, and how to solve them? Weehee, I love you acid base.</p>

<p>A steady electric current is passed through molten MgCl2 for exactly 1.00 hour, producing 243 grams og Mg metal. If the same current is passed through molten AlCl3 for 1 hour, the mass of Al metal produced is closest to </p>

<p>a) 27.0 g
b) 54.0 g
c) 120 g
d) 180 g
e) 270 g. </p>

<p>it’s D. WHY?</p>