<p>hmm. I would say 2HNO3. I’m not really sure why, but it seems the most stable. I’d like to hear someone else explain this better too, because I don’t know how to tell about these.</p>
<p>One to watch out for is H2CO3 which breaks into H2O and CO2 ALWAYS.</p>
<p>tmanneopen, thank you very much for your explanation! It was very clear, and I’m sure I can get at least half of the question right now just from reading that for 30 seconds. =] I’ll read a little more and practice a few problems…I guess they wouldn’t use a whole sheet of paper in our reference table for something we won’t have!</p>
<p>Hahaha, I’m glad I could help. If you need anymore explanation about electrochemistry, let me know 
And yea, that sheet will definitely come in handy :)</p>
<p>Ok you guys might laugh at my lack of understanding for chemistry but can anybody explain why a spare pair on a lewis structure of a compound indicates a dipole moment? I thought that a dipole moment happens when one element that is more electronegative than the other and thus draws electrons to make one end more negative than the other. So if there was a spare pair on one element, then why would the dipole moment head in that direction? (As in, the structure would be negative in the direction of the element with the spare pair) when electrons repel other electrons so wouldn’t the electrons…head in the other direction…</p>
<p>I don’t understand your question. It sounds too complicated for AP chem though (I hope!)</p>
<p>Well basically, my question is why do spare pairs indicate a dipole moment?</p>
<p>I guess I worded it too much haha xD</p>
<p>^Dipole moments are created from asymmetrical molecules. A spare pair of electrons create angular molecule shapes like bent and prevent them from being symmetrical, therefore creating dipole moments. </p>
<p>Hope that helps</p>
<p>How does Ksp work? My teacher said that might be question #1 this year?</p>
<p>ahh ok that makes sense. So it’s basically because a spare pair creates uneven charge distributions, right? Thanks!</p>
<p>also, I have one moree question (all of my posts on this thread have been questions so far, i feel like a parasite or something… lmao) </p>
<p>How are you able to distinguish what kinds of IMFs certain molecules have? </p>
<p>I know that
London dispersion forces= nonpolar
Hydrogen Bonding= when H is attached to F,O,N
Dipole-dipole= polar</p>
<p>but how can you tell if a compound will be a network solid or ionic solid?</p>
<p>A solution of barium chloride is added drop by drop to a solution of sodium carbonate, causing a precipitate to form.</p>
<p>I don’t understand how to write the equation for this… Also, why is NaCO3 considered a base?</p>
<p>Ksp just tells you the equilibrium constant for a substance dissolved in water (usually) based upon the substances ions. You can also find out how much of the substance can dissolve in the water by solving for it.</p>
<p>For example:</p>
<p>PbCl2 -> Pb+2 + 2Cl-</p>
<p>Ksp ([Pb+2]^1)([Cl-]^2) = 1.6 x 10^-4</p>
<p>You raise each ion to the number of moles it creates when it goes into solution.</p>
<p>You would solve for it like this:</p>
<p>[x (Pb+2)][2x (Cl-)]^2 = 1.6 x 10^-4
4x^3 = 1.6 x 10^-4
x = 0.034</p>
<p>The reason why you have 2x for the chlorine is that for every mole of lead, you have two moles of chlorine, so you have to account for that.</p>
<p>So in the above example, 0.034 moles of PbCl2 can dissolve into water before any starts precipitating.</p>
<p>
</p>
<p>hydrolysis, Na is NaOH, which is a strong base, HCO3 is a weak acid.</p>
<p>Thank you tmanneopen.</p>
<p>@Iamcool: Usually only compounds with just carbon or SiO2 (quartz) are network covalent. I’ve never seen any other types asked about. For ionic solid, it’s just if the difference in the electronegativities is greater than 1.7. You can also tell if it’s a combination of a metal and nonmetal.</p>
<p>@zzxjoanw3: Just replace lead with barium in my example and that should explain it.</p>
<p>@SamirBabai: No problem :D</p>
<p>@zzxjoanw3 </p>
<p>write out the whole reaction first
so BaCl2 + Na2CO3 -> BaCO3 (s) + NaCl
this is double replacement
use your solubility rules and you’ll see that BaCO3 is a a ppt or a solid and because the formation of a precipitate is the driving force for this reaction, you would write the net ionic reaction as
Ba2+ + CO32- -> BaCO3 (s)</p>
<p>
Should be:</p>
<p>BaCl2 + Na2CO3 -> BaCo3 + 2NaCl</p>
<p>Net Ionic:
Ba2+ + CO32- -> BaCo3</p>
<p>ahh tmmanneopen you beat me to it haha</p>
<p>and thanks! so basically, network solids must be memorized then right?</p>
<p>A 8.8g mixture of methanol and ethanol is completely combusted with oxygen and yields 14.020 g of carbon dioxide gas. </p>
<p>2CH3OH + 3O2 -> 2CO2 + 4H2O
CH3CH2OH + 3O2 -> 2CO2 + 3H2O</p>
<p>Calculate the percent composition by mass of methanol in the mixture</p>
<p>Molar mass of methanol = 32.0426 g
Molar mass of ethanol = 46.0694 g</p>
<p>Anyone? o_o"</p>
<p>Hahaha, yea. Just look up a few and you should be fine. On second thought though, I didn’t answer all of the question, so thanks for posting, haha.</p>
<p>I think this is actually helping me review a lot. I made a bet with my teacher that I’m going to get a 5, so keep asking those questions :D</p>
<p>Whenever you see a metal made btw a metal and nonmetal you know its an ionic solid. </p>
<p>Networks solids are made btw two nonmetals and have high melting and boiling points.</p>