<p>Hey guys, just figured this would be useful for the exam in a couple of weeks since not many posts have been made about AP chem. Discuss FRQs, possible topics that could show up, how you're studying, etc. Good luck everyone!</p>
<p>Ok, I’m a noob at this website, so idk if this is the right location for this post:
Lots of questions just give you four or five molecules and just ask you specific things regarding their shape, like molecular geometry, # of pi bonds, etc. But the only way I know to solve these problems is by drawing a structure for each option, but obviously that takes waay too long. </p>
<p>So does anyone have any tips on answering these questions?</p>
<p>Just memorize those tables in your textbook. It’s not too hard. Locate the central atom (the atom without subscripts) and find how many substituents are attached (count the other things next to the central atom, including subscripts).</p>
<p>For example: CH4. Carbon is the central atom (it doesn’t have subscripts), and there are 4 substituents (4 hydrogen atoms). If you have memorized those tables you would know that something with 4 things attached is tetrahedral, sp3 hybridized, has bond angles of 109.5°, etc. It gets a bit trickier with lone pairs but these should be accounted for in the tables in your textbook.</p>
<p>Each double bond has 1 pi bond and each triple bond has 2 pi bonds. For example, some molecule with 2 double bonds and 1 triple bond has 4 pi bonds. For these it’s best to draw them out unless you have lots of experience.</p>
<p>do you guys think barron’s is overly hard? i seem to understand all of the material and just get to the back of each chapter and im like what i dont know any of this</p>
<p>same here, I gave up on barrons and moved to Princeton review, but apparently thats too easy, so now im cramming on a pdf of 5 steps to a 5 which can be found with a quick google search.</p>
<p>Not to steal any thunder, but my thread here may be of some assistance. </p>
<p><a href=“http://talk.collegeconfidential.com/ap-tests-preparation/1376986-official-ap-chemistry-2013-thread.html[/url]”>http://talk.collegeconfidential.com/ap-tests-preparation/1376986-official-ap-chemistry-2013-thread.html</a></p>
<p>Maybe this thread can be used as a cram thread if mine gets too large to sort through</p>
<p>Let’s make this a REAL study thread! >:]</p>
<p>Don’t CHEAT. You’re only cheating yourself. :)</p>
<p>I’ll start off easy with this question. This should take no more than 30 seconds. </p>
<p>*The standard reduction potential for Zn2+ + 2e- ==> Zn, is -0.76 V, and the standard reduction potential for Fe3+ + e- ==> Fe2+, is +0.77V. What is the Ecell for the reaction below?</p>
<p>2Fe3+ + Zn ==> Zn2+ + 2Fe2+*</p>
<p>Is the answer 1.53 V?</p>
<p><em>claps</em> Congrats, thelemonisinplay!</p>
<p>Second question!
Time: 30 seconds </p>
<p>*One of the following assumptions is NOT part of the kinetic theory. Which one?</p>
<p>(A) The particles in a gas have a negligible volume
(B) The particles in a gas are not attracting one another
(C) The particles in a gas collide with one another in elastic collisions
(D) The speed of the particles in a gas is directly proportional to the Kelvin temperature
(E) The particles in a gas cannot be compressed*</p>
<p>E?
10char…</p>
<p>Correct, Taco! (You make me want some Mexican food right now…)</p>
<p>*In an equilbrium reaction that has been catalyzed, all of the following statements are true, EXCEPT;</p>
<p>(A) In the catalyzed reaction the rate of both the forward AND backward reactions are increased
(B) In the catalyzed reaction equilibrium will be achieved more quickly
(C) The catalyst will be unchanged at the end of the reaction
(D) In the catalyzed reaction K for the forward reaction will be larger
(E) The catalyst will have the effect of providing a reaction pathway with a lower activation energy*</p>
<p>D? Or B? hmmm. I’m quite sure its one of them…
Gonna go with D.
Are yuo getting these from previous tests?</p>
<p>I also pick D for the equilibrium question.</p>
<p>D, since a catalyst only lowers the activation energy, thus speeding up both reactions, right? I’m really worried about this AP exam…:’(</p>
<p>Sent from my HTC6435LVW using CC</p>
<p>I pick D because K is only temperature dependent, right?</p>
<p>Here’s another:</p>
<p>Appropriate uses of a light spectrometer include which of the following?
I. Determining the concentration of a solution of Cu(NO3)2
II. Measuring the conductivity of a solution of KMnO4
III. Determining which ions are present in a solution that may contain Na+, Mg2+, Al3+</p>
<p>(A) I only
(B) II only
(C) III only
(D) I and II only
(E) I and III only</p>
<p>The correct answer is D. Great job, guys! </p>
<p>*Which element would be expected to exhibit the greatest difference between its second and third ionization energies?
(A) Mg
(B) Al
(C) P
(D) S
(E) Cl</p>
<p>Bonus Question:
What type of reaction is occurring here?
[Cu(H2O)6]2+ + 4NH3 ==> [Cu(H2O)2(NH3)4]2+ + 4H2O
(A) Acid/Base
(B) Complex ion formation
(C) Neutralization
(D) Redox
(E) Ligand exchange*</p>
<p>A. Mg
I think it’s because on the second to third ionization energy, Mg goes from a noble gas (Ne) to (F). It’s not going to want to give away an electron so easily when it’s already stable.</p>
<p>Great reasoning! Do you want to take a crack at the bonus question? (It’s not common and most likely will not show up on the actually AP exam).</p>
<p>Which indicator is suitable for use when titrating a strong acid with a weak base?
(A) Phenolpthalein
(B) Methyl Orange
(C) Litmus
(D) Any indicator
(E) None of the Above</p>
<p>Niquii, i was actually just studying today and my barron’s book said that catalysts increase the value of k? could you please explain this? thank you!!!</p>