<p>I'm taking it during the late testing day (this Thursday) and I need some help.</p>
<p>Do I have to memorize all the fancy equations for the multiple choice? Like -2.178 X 10^-18/n^2 and whatever that other equation is for nonstandard Gibbs energies?</p>
<p>Or should I ease off the memorizing of formulas and just go for concepts?</p>
<p>Lastly, I just noticed this: PCl5 and SF6 are both legit molecules, but neither P nor S has any d orbitals. How is that possible?</p>
<p>I took it junior year, but from what I remember: go for concepts. Just make sure that you know the basic equations, but remember that you don’t need to know all the equations.</p>
<p>I just took the test last Tuesday. The formula sheet isn’t given to you for the multiple choice, but I don’t think you will need it. You aren’t given a calculator, so many of the constants will not be able to be used without a calculator. And most of the formulas you should know are simple ones like MV=MV, delta G=delta H - T delta S, etc.</p>
<p>And for PCl5 and SF6, they are 3rd period elements so they can fit extra electrons in the 3d orbital. They don’t necessarily have to have 3d electrons in there. And 3rd period element are larger can have an expanded octet.</p>
<p>Yes, a conceptual understanding is certainly of greater consequence on the multiple choice portion of the exam. However, many of these questions will depend on a basic, qualitative understanding of the equations. So, for the most beneficial outcome, I would recommend that you commit the given equations not simply to memory but to have a working knowledge of their function and applicability.</p>
<p>The equations that you should know for the multiple choice include:
M1V1 = M2V2
delta G equation
freezing point depression/boiling point elevation
Ksp, Ka, Kb
combine gas law (and ideal gas law?)</p>
<p>I can’t think of any other at the moment.</p>
<p>bohr’s equation isn’t on the sheet, I don’t think it is on the exam</p>
<p>yeah just remember the basic concepts, not the complicated formulas</p>
<p>these would include the van hoff’t factor
non-ideal gas formulas
and other equations that look way too complicated
the only “complicated” formulas you should know are the Nernst Equation and the Henderson-Hasselbach equation</p>
<p>oh and phosphorus and sulfur do have D orbitals
periodic tables are a bit misleading
the transition orbitals of the fourth row are actually 3d, which allows P and S to form molecules such as SF6 and PCl5</p>
<p>did anyone else find the mc questions in the chem course description packet to be extremely hard…?? i got 10 wrong out of 29…</p>