May 2013 SAT II Chemistry

<p>wait for the question that measured the pressure, did it ask fro the pressure of the gas or the atmosphere</p>

<p>I found it harder than the Blue Book practice. </p>

<p>I also got 4 CE’s and a load of T/F’s. i’ll post a list of questions I remember when I get home.</p>

<p>Yeah, it was significantly harder than the blue book test.</p>

<p>I hope the curve is consequently more generous… -4 raw or better for 800?</p>

<p>what was the answer to the question with the water cooling down graph? was it the parabola ->horizontal line -> diagonal line going down? I thought so because the horizontal line was needed for the pahse shift</p>

<p>Here are a few questions I jotted down after the test:</p>

<p>-NaCl crystals added: no concentration change? (unsure of this one)
-Kinetic molecular theory: constant speed? (also unsure)
-T/F/CE question on oxygen and hydrogen (?) and the volumes they occupy; first part was T, second I think was F (said all ideal gases have particles that move at the same speed)
-T/F/CE question on combustion enthalpy: F/T (combustion reactions are NOT endothermic, and the products DO have less enthalpy than the products).
-Bronsted acid/base reaction: HCl + NH3 → NH4Cl
-Ionization energy question (with the table): nitrogen family
-3.6 g H20 formed on question 69
-720 mm Hg was the pressure of the gas in the eudiometer
-V0/2 was the new volume (after pressure was doubled)
-Halogens contain the red liquid (Br2) at STP
-He gas volume for question 68 was 89.6L
-Freezing of H20 is exothermic and decreases entropy
-Addition of Na2SO4 lowers [Ca2+] at equilibrium (the reaction was CaSO4 → Ca2+ + SO42-).</p>

<p>I remember a few other really easy ones (like number 70), but they’re not really worth posting. I’m mostly uncertain about the first three questions I listed above. If you have any input, do share it.</p>

<p>@chemmy
It asked for the pressure of the gas. I put 720 mmHg. I think that’s correct.</p>

<p>@bugacuga: Yes, the graph with the horizontal line was correct.</p>

<p>kinetic molecular theory wasn’t speed, it was the same kinetic energy. what was the question for the nacl one? i remember one answer was something like .2 M and the last question pretty much asked for the definition of molarity. what was the he gas question too? and btw i remember getting an alpha particle for some nuclear reaction</p>

<p>I thought one of the choices for KMT was collides with other gas particles and the walls of the flask (chose that one).</p>

<p>@diddly: NaCl question had a saturated solution into which a crystal of NaCl was added. I said the concentration remained the same. The He question asked for the volume of 2 mol He gas at .5 atm and 0 degrees Celsius. </p>

<p>I just remembered another: the alpha/beta/gamma one had beta going toward the positive side, alpha going toward the negative side, and gamma right in the middle. I believe alpha was at position 1, gamma at 2, and beta at 3, though I’m not totally sure.</p>

<p>@jjfine: KMT states that the volume of each particle is 0 and thus implies that the gas particles do not collide with one another (or at least do not exert any forces on the other particles). I was really unsure on that one, though. I’m probably at -2.</p>

<p>was 69 the one with the h20 3.6 for sure?</p>

<p>what was the answer to the question with the water cooling down graph? was it the parabola ->horizontal line -> diagonal line going down? I thought so because the horizontal line was needed for the pahse shift</p>

<p>Weren’t there two similar graphs for this one? One was a decreasing curved line, horizontal line, decreasing curved line and another a decreasing curved line, horizontal line, straight line w/downward slope?</p>

<p>And yeah it was alpha/gamma/beta</p>

<p>From <a href=“http://chemed.chem.purdue.edu/genchem/topicreview/bp/ch4/kinetic4.html:[/url]”>http://chemed.chem.purdue.edu/genchem/topicreview/bp/ch4/kinetic4.html:&lt;/a&gt;&lt;/p&gt;

<p>These particles move in a straight line until they collide with another particle or the walls of the container.</p>

<p>wait why would the concentration not increase? if you added more solute to a saturated solution then no more can enter solution. it’ll just sit in the container, so the concentration would increase… thats what i thought but idk now</p>

<p>what did you guys get for the most temperature change and they listed different heat capacities? Was it the largest number or smallest?</p>

<p>i put the smallest^ because heat capacity is the amount of energy it takes to raise the temperature. if you have the smallest heat capacity, then you don’t need much energy to raise your temperature. so thus it’s the smallest</p>

<p>@diddly123 the NaCl would have to dissolve (Na+ and Cl-) for the concentration to increase; given it’s already saturated it wouldn’t dissolve so concentration shouldn’t change.</p>

<p>@penelope123 It was the smallest J/g*C value; I think the answer was Hg.</p>

<p>wait why would the concentration not increase? if you added more solute to a saturated solution then no more can enter solution. it’ll just sit in the container, so the concentration would increase… thats what i thought but idk now</p>

<p>I believe what they were getting at is the concentration of the ions in the solution would not increase, the concentration of ions would remain the same (because it is saturated so it can’t hold any more) and additional solid would form.</p>

<p>@jjfine: Yes, but I think the choice said something like “exert forces on other particles,” which KMT assumes doesn’t happen. The “move in a straight line” choice was confusing to me, though. I’m not sure it was the best-written question.</p>

<p>@BeccaN: But no more NaCl is dissolved, so the concentration of NaCl in solution is the same.</p>

<p>(I know, I was answering the question and forgot to include quotes. The para above was not written by me, sorry if that was unclear!)</p>