**OFFICIAL** AP Chemistry 2014 Thread

<p><a href=“Live video chat rooms, simple and easy. - Tinychat”>Live video chat rooms, simple and easy. - Tinychat; , guys i just made a chat room, lets answer each others’ questions. college confid. kinda not the best thing to have a smooth conversation.</p>

<p>@spherescholar The thing is the curve isn’t based around how WE (the HS students taking the test do) but around how College students would do if they took the test. So a 5 is meant to tell a College that if this student took the class he would earned a A- (i think is A- not sure) or higher. Therefore predicting the curve is really hard but I still think if you get more that 66% to 70% of the test right you should get a 5.</p>

<p>I was watching the those videos that were suggested, and it was stated that a carbon to hydrogen Bond (as in methane) is nonpolar covalent. Can someone explain how to different atoms can form a nonpolar covalent Bond? </p>

<p>Also, a lot of times, he talks about one molecule/compound having a higher charge than another (then relates to Colombs law)… What is the higher charge, aren’t compounds neutral? </p>

<p>in relations to Coulomb’s law, q is the charge of each individual ion. each ion is charged but the compound they form is neutral</p>

<p>Okay, thanks, any answer on my first question?

I was watching the those videos that were suggested, and it was stated that a carbon to hydrogen Bond (as in methane) is nonpolar covalent. Can someone explain how to different atoms can form a nonpolar covalent Bond?</p>

<p>@jamesjunkers‌ It’s nonpolar since there isn’t any lone electron pairs. Well, that’s one reason at least. The electrons have to be distributed somewhat equally. And if you draw the less structure, it should be symmetric.</p>

<p><a href=“http://media.collegeboard.com/digitalServices/pdf/ap/2013advances/AAP-ChemistryCED_Effective_Fall_2013.pdf”>http://media.collegeboard.com/digitalServices/pdf/ap/2013advances/AAP-ChemistryCED_Effective_Fall_2013.pdf&lt;/a&gt;&lt;/p&gt;

<p>@jamesjunkers C and H have basically the same electronegativity. Polarity is determined by the difference in negativities. Anything with a difference of less than 0.4 is considered nonpolar.</p>

<p>The Barron’s practice exam seemed very simplistic to me (hopefully the exam will be like that <em>crosses fingers</em>) I got 86% on the multiple choice.</p>

<p>@meaa7130, that would make the molecule nonpolar, not the bond
@Theswimmer, how can I measure the EN difference if not given values? </p>

<p>Could anyone message me the vspr shapes we need to know. I lost my notes and whenever I google it I get overly complicated lists. Thanks and good luck to everyone on Monday</p>

<p>Hey guys, what score would I get if I got all the multiple choice right, but got all the free response wrong??
So far, I see little hope for the FRQs…I need to review all my laws and principles lol</p>

<p>@KbbGrizzly You’d be getting a 50%. New test and old test alike, a score like that would probably get you a 3 regardless of the new curve. </p>

<p>@jamesjunkers My teacher told us that if there is more than 2 column/groups in between, it’s polar. If not, it’s nonpolar. (that’s really not completely true though) So if you took out the transition metals, there would be 2 column in between C and H and it is nonpolar. You really just have to know it.
<a href=“http://www.mikeblaber.org/oldwine/chm1045/notes/Bonding/Polarity/e_neg2.gif”>http://www.mikeblaber.org/oldwine/chm1045/notes/Bonding/Polarity/e_neg2.gif&lt;/a&gt;&lt;/p&gt;

<p>what would be the percentage for a score of 4?</p>

<p>@KbbGrizzly Based on the 2008 curve, which, for the mid-range scores, would probably still apply to the new test, the cut-off for a 4 would be a 53%. Basically, IF you were to get all of the multiple choice right, you would theoretically only need about 3-4 points of the FR to get a 4. However, I obviously don’t know what the curve will be like, so don’t take my word for it. </p>

<p>Is the lab section in Barron’s good preparation for the lab FRQ?</p>

<p>Guys, just relax. It’s a new test, so it should have a pretty nice curve. Barron’s said that 67 points out of the total 101 points is a 5. That’s a pretty nice curve. If you can nail it the FRQ’s and do pretty well on MC, then you’re fine. &lt;/p>

<p>Here’s a link for anyone who needs help with organic chem:
<a href=“Understanding the names of organic compounds”>http://www.chemguide.co.uk/basicorg/conventions/names.html&lt;/a&gt;&lt;/p&gt;

<p>@Hawkace Barron’s has no idea what the actual curve is. That curve (and they might have even said this) was based off of the curves of the previous tests. 67/101 is a 66% which we seemed to have established as what the average curve for the older tests was. </p>