<p>isn’t unimolecular sn2?</p>
<p>D’oh got the shielding one wrong. 58 max now…</p>
<p>Wait what?? 33 was the hydrazine/methylamine/ammonia/hydroxylamine basicity question. I checked and methyl amine has the lowest pKb. 45 was the photoelectric effect question.</p>
<p>For aluminum hydroxide and HF, wouldn’t it form AlF6 3- as in cryolite? Cryolite is unreactive with water so the ion is stable.</p>
<p>Iodide just catalyzes the decomposition of hydrogen peroxide while forming a small amount of I2 and OI- as catalyst. OH- actually causes iodine to disproportionate into iodide and iodate. This effect is greater at higher temperatures (and decomposition of H2O2 is strongly exothermic). So KI is just a catalyst.</p>
<p>Would HCl not protonate the hexamethylenediamine and form a salt? I didn’t put that but it’s just a possibility. Oh god I might have forgotten to write HCl… Too busy drawing the structure…</p>
<p>For the decreasing ionization energy one, I wrote that higher energy levels are closer in energy than lower energy levels.</p>
<p>If you have a polar protic solvent like water, it may act as the nucleophile and cause an SN2 reaction. A polar, aprotic, non-nucleophilic solvent would probably be best (I might have written something else on the test).</p>
<p>Side note: If branching affects carbocation stability, I wonder how stable a tris-(tert-butyl) carbenium ion would be…</p>
<p>For the manganese cell + barium one, I messed up because I thought the increase in H+ (which has coefficient 3) would offset the decrease in the ratio of bisulfate to sulfurous acid and increase the voltage…</p>
<p>@youtwothirtyfive
i think i read the question wrong and my mind jumbled up unimolecular with uni-step mechanism or something -_- but if it was talking about sn1, then you’re right. sn2 definitely requires aprotic tho</p>
<p>No, unimolecular is SN1, that’s what the “1” in Sn1 stands for… “uni”
You should have a polar protic solvent because aprotic favors Sn2. Protic solvents create a solvent shield around the nucleophile but in Sn1, the rate of reaction is just determined by the electrophole I think.</p>
<p>ah, you’re right on both of those reactions. I think they’d still give full credit for the iodide question if you did redox. forgetting HCl will probably be -0.5 pt lol D:</p>
<p>Yeah, that’s an equivalent way of saying d electrons are poorer shielders, i think? lol</p>
<p>hmm, perhaps but orgo textbooks kinda beat it in to you that polar protic is good for sn1?</p>
<p>@thenerdyjew–Hmm I got 24.6 for my percent ethanol, same as YouTwoThirtyFive.</p>
<p>@barley81–I think the photoelectric effect was wave/particle duality for light (see Photoelectric effect - Wikipedia; search for Einstein). I thought reaction 6 was looking for a acid/amine–>amide reaction, so I just left the Cl- part out. Oh and I wrote that it condensed water.</p>
<p>What was the answer for the HCl increasing solubility descriptive question?</p>
<p>@thenerdyjew
I remember the mouthwash question gave an aliquot so you would have to multiply it by some number to get the % in the WHOLE sample</p>
<p>Well there goes making camp…</p>
<p>@dobboyshi, the anion was hydrogen phosphate</p>
<p>@YouTwoThirtyFive–ah shoot. I had that then changed it to something else. Oh well.</p>
<p>@YouTwoThirtyFive:
You’re right about the Sn1 thing. Water’s not a good nucleophile. I don’t remember my response though.
Man, my mental score keeps dropping… Ugh.</p>
<p>@dobbyoshi</p>
<p>If I remember correctly, lowering the pH would affect the solubility of a salt with a weak acid anion and it should be CaHPO3 because HPO3-2 is the conjugate of the weak acid H3PO4.</p>
<p>Does anyone remember the answer to the MC calorimetry problem dealing with ice?</p>
<p>Lol if we’re all doing worse then we had envisioned, it’s all relative so 55+ and 88+ won’t be necessary for study camp</p>
<p>@ Sophia, -56 degrees</p>
<p>Maybe my mind is just screwed up but wasn’t it asking for q(heat) of the ice?</p>
<p>I remember there was one on the MC that was like:
dG = 4.265 kJ/mol at 298K for CH3OH (l) → CH3OH (g)
I did G = -RTlnK, then found K to be 0.178, then i wrote the K expression
K = 0.178 = Pressure of CH3OH(g)
so then 0.178atm is the pressure = 136 mmHg (134 was one of the choices).
is that what you guys got?</p>
<p>@Sophia, I got something like -33 deg C</p>
<p>@Sophia7X–I think that I remember it asking for the temperature at which the ice started. But then again I think all of our minds are perhaps a little fried…</p>
<p>@thenerdyjew–I got 136mmHg/134 or whatever it was too.</p>
<p>@YouTwoThirtyFive, you forgot to add 21.3 to your answer. It was -56 = T - 21.3, so T is something like -34 or -33</p>
<p>oh now I remember. I just remember what number I had… I knew it was thirty something.
And I got the 0.178 ATM but why did you convert to mmHg? Kp is measured in atm</p>
<p>@ thenerdyjew, ah you’re right. 57 MC now :((</p>
<p>now that I think about it that MC was pretty evil</p>
<p>Kp is supposed to be given in atmospheres. that is 0.178 atm, which is in turn 135 mmHg.
All the answer choices were given in mmHg (which is the customary unit for vapor pressure)</p>