<p>I think ur wrong about the isomer i looked it up on wikipedia and got</p>
<p>isomers are molecules with the same chemical formula and often with the same kinds of bonds between atoms, but in which the atoms are arranged differently. That is to say, they have different structural formulae</p>
<p>But might be my bad i meant chemical formula</p>
<p>^Trust me hes right because I am taking AP chem and they ARE both isomers.</p>
<p>Isomer just means they have the same elements and the same number of each element, but are arranged differently. You were looking at the structural formula in the drawing, but the chemical formula of each would be (don't remember exact number of molecules, but) C3H8 for example</p>
<p>Are u sure they both had the same number of hydrogens because I think one had 7 and one had 8 which means they are not isomers</p>
<p>^They definitely had the same number of hydrogens and carbons. TTCE</p>
<p>Ty everyone for your posts, sry if it was any inconvenience
now thats cleared up (apparently i counted wrong sry)</p>
<p>And for the PV/T q, the starting pressure was definitely 1.5 atm. 100percent sure because I suk at calculations and checked like 5 times to make sure 8 x 1.5 was really 12.</p>
<p>And for the question with the reaction diagram, did you guys get F/T?</p>
<p>oh I remember that part of the 1.5 question now, does anybody know exactly what the question was?</p>
<p>Basically asked for the new volume, 1.5atm x 8L/ 200K= .5atm x V/ 100K
Answer was 12L, dont remember if I put that though.</p>
<p>I don't remember what I put...hope I got it right</p>
<p>Yea, I got it wrong, I now remember putting 6L, cause i was ignoring the pressure.</p>
<p>no it was 8L, it didnt change</p>
<p>the pressure decreased from 1.5 atm to .75 atm and the temperature went from 100K to 200K</p>
<p>Ok, Yea nvm, I definitely remember it being .75atm now. Btw, was the answer choice 8L, or was it "stays the same"? Cause if it was 8L then I tihnk I mightve gotten that.</p>
<p>8L was the answer</p>
<p>Time for another one! Wow we actually remember a lot of the questions!!!</p>
<ol>
<li> How limestone reacts with acid rain (neutralization because limestone is Ca(OH)2 and when you pour an acid onto that it'll probably neutralize
limestone is a base and acid rain is an acid)</li>
<li> NaF, NaCl, NaBr, NaI, NaAt: either highest melting point or lowest melting point (NaF)</li>
<li> Potassium and water (forms OH- and H2)</li>
<li> Iron filling and sulfur powder (magnet and cardboard)</li>
<li> NaCl and water (condenser and distillation)</li>
<li> Different ink (chromatography)</li>
<li> An electron in a radioactive reaction; electrons dont take up 1/3 mass (I and II)</li>
<li> K+ and Na+ are not isotopes</li>
<li> Diamond and graphite have the same structure because the are both pure forms of carbon
not the same structure (F/T)</li>
<li>I. CO2 has polar bonds but is not a polar molecule II. CO2 has linear structure. (TTCE)</li>
<li>Cs is the most reactive in water because it is an alkali metal</li>
<li>Which one isn't in the elemental state (Na)</li>
<li>O2 and O3 what are they? (allotropes)</li>
<li>CO2 forms an acid but not a STRONG acid</li>
<li>Collection of gas over water: O2 and H2 only (no HClsoluble in water)</li>
<li>Brittle, could conduct electricity when melted (ionic bond)</li>
<li>Water boiled at a lower temp at higher altitudes and air pressure is lower at higher altitudes. (True b/c water boils at lower temp. but false b/c pressure is lower at higher altitudes) (T/F)</li>
<li>Limiting reagents question: 1A + 2B -> 1AB2 there was 500 milliliter .1 molar solutions mixed together, how much product was formed</li>
<li>Vanadium: VO2 if you have 5.1 grams of vanadium and its oxide form weighs 8.3 grams, what is the formula?
5.1 g is .1 mole of Vanadium and the rest 3.2 is 10% of 32 grams (the weight of two oxygen atoms).</li>
<li>HgI2 + H2S --> HgS + 2HI or HgCl2 + H2S --> HCl + HgS2 or Hcl + hgs in products (I because it was definitely Hg(2) in the reactants since it was HgCl2. And since S is (-2), then the subscripts will cancel out so HgS and it does not need any coefficients.)</li>
<li>Lab question: cant heat graduated cylinder</li>
<li>How many unpaired electrons could fit into a p orbital (3)</li>
<li>0.05 on PbI2 (precipitate)</li>
<li>65 grams for something</li>
<li>I. [picture of hydrocarbon] is an isomer of [another picture] II. isomers have the same molecular formula but different structures (TTCE)</li>
<li>3 for oxidation one (nitrogen family)</li>
<li>temperature cannot be used to use ideal deviation</li>
<li>heat of sublimation (solids to gas)</li>
<li>22.4 for one of them</li>
<li>11.2 for the other gas one (2 atm, NO2, 273K)</li>
<li>Cl- stronger oxidizing agent than S</li>
<li>C to CO2 oxidization (0 to +4)</li>
<li>The one where temperature decrease from 200K to 100 K, pressure increases, then they ask for the volume. (1.5 atm)(V) / (100K) = (0.75 atm)(V)/(200K) (the volume remains the same at 8L)</li>
<li>There was a reaction asking what the oxidation states changed for Nitrogen in the reaction (+5 to 3)</li>
<li>Does not something to temperature (density)</li>
<li>London dispersion forces for the Nitrogen question</li>
<li>H2O is NOT a strong electrolyte (so I and II only).</li>
<li>Gases are more compressible than liquids, fewer intermolecular forces (T/F)</li>
<li>How many covalent bonds did propane have? 10</li>
<li>Fe2(SO4)3 dissociates into 5 mols of ions</li>
<li>Degree of acidity (indicator)</li>
<li>I. NaOH forms a basic solution II. It dissociates into OH- ions. (strong base so TTCE)</li>
<li>Is it possible to emit a particle with a negative charge in a nuclear reaction? (yes-beta decay)</li>
<li>I. Iron mesh rusts faster than iron block of the same mass. II. Iron mesh has greater surface area (TTCE)</li>
<li>Spectator ions: Cl- and Na+</li>
</ol>
<p>Question(s):
1. Coefficient of PbI2 (or how much was formed)? Balancing equations question (or stoichiometry)
2. Lowest coefficient for that equation with the CaCO3
3. Question with the reaction diagram (F/T)???</p>
<p>No. 27- could be density if the problem specified constant volume</p>
<ol>
<li>Question with the reaction diagram (F/T)???
yes, definitely F/T
First statement said the reaction was endothermic, which is false.</li>
</ol>
<ol>
<li>temperature cannot be used to use ideal deviation</li>
</ol>
<p>I disagree with that one. Temperature does affect ideal gas deviation because it affects the attractions between molecules. </p>
<p>Proof: From this website
<a href="http://wine1.sb.fsu.edu/chm1045/notes/Gases/Deviate/Gases10.htm%5B/url%5D">http://wine1.sb.fsu.edu/chm1045/notes/Gases/Deviate/Gases10.htm</a> </p>
<p>It says that "deviation from ideal behavior is also a function of temperature"</p>
<p>Density is not affected by temperature though. Think about the equation for density, g/mL. Temperature affects neither the grams you have or something or the volume and volume was kept constant.</p>
<p>Isnt 27 and 35 referring to the same q?</p>
<p>Yea, he's right. The answer was density.</p>
<p>I found the test to be harder than barron's and pr's, but i could be crazy.</p>