CHEMISTRY COMMUNITY

Wenqian_Deng_1L

Why do aromatics belong in the nuthouse?

Because they are CYCLO. hahahahahah rip lol.

Wenqian_Deng_1L

Dr. Lavelle, Thank you for being such a superb and caring professor! The hours of preparation and organization of the lectures, course readers, and all of the resources is greatly appreciated. I came to college not looking forward to taking chemistry courses because in high school, AP chemistry neve...

Wenqian_Deng_1L

And since this is not an addition reaction, it must be a SN2 (bimolecular nucleophilic substitution) reaction, because that's the only two reactions we've gone over in the course reader.

Wenqian_Deng_1L

Yes, @kira, if we have a reactant that shows up as a final product, we know it is a catalyst because it was not an intermediate that was "used up" in the reaction.

Wenqian_Deng_1L

When given a two chemical reactions, and we know that one is slow and the other is fast, the problem should either give us clues to determining which is which. For example, the problem could say that the equilibrium constant (k1) of one reaction is slower than the equilibrium constant (k2) of the ot...

Wenqian_Deng_1L

I think the problem would state that the reaction will occur at constant temperature so that we know which equation to use.

Wenqian_Deng_1L

What about when we're asked to find the temperature of a first order reaction? When we switch the first order integrated rate law to solve for temperature, the negative sign of the rate constant (K), disappears. Am I doing algebra wrong or does it just conveniently cancels itself somehow?

Wenqian_Deng_1L

Does changing the temperature also affect the catalyst, which then affects the activation energy and the rate constant?

Wenqian_Deng_1L

Does this mean that we would still need to identify the oxidation states of each element?

Wenqian_Deng_1L

It doesn't ALWAYS have to be platinum, the course reader just used Pt as an example.

Wenqian_Deng_1L

My TA reviewed the equations sheet that will be given to us for the quiz and he said that almost all the equations we need are on the sheet. The only equation we need to memorize is the one that calculates work when it's a reversible isothermal reaction, which is w = -nRT ln(V2/V1)

Wenqian_Deng_1L

YUP to all the explanations above. When an equation is at equilibrium, it just means that the forward reaction is the same rate as the reverse reaction, and both products and reactants are still being produced.

Wenqian_Deng_1L

Do we use the Heisenberg-Hasselbach equation only when we are given a buffer solution problem? Or does it work when you just have all the information to plug in?

Wenqian_Deng_1L

When we have a heteronuclear molecule (z>8 in one atom and z<8 in second atom), then we stick with the z<8 MO diagram. At least that's what the TA told us.

Wenqian_Deng_1L

No I don't think so. However, usually when there's a strong conjugate acid/base, the "second step" of the equation involves the conjugate acid/base to take a proton from water and reform into it's original base/acid, and making the solution either basic or acidic.

Wenqian_Deng_1L

I don't think we need to memorize the type of indicators since they'll be listed for us, like how it was in one of the practice final exams.

Wenqian_Deng_1L

So when do we use bis-, tris-, tetrakis-, pentakis-, etc?

Wenqian_Deng_1L

All the equilibrium constants will be given to us in during the test, so we don't have to memorize them! (:

Wenqian_Deng_1L

Also Shrodinger's wave equation shows that electrons also have wavelike properties.

Wenqian_Deng_1L

But we do need to know that Kw = 10^-14.

Wenqian_Deng_1L

So does that mean we have to draw the Lewis structure of the molecule to see if it has a dipole moment?

Wenqian_Deng_1L

For heteronuclear molecules (like NO), we always stick with the MO diagram for z<8. That's what the TA told us when we went his review.

Wenqian_Deng_1L

@Joanne I think we have to take into account that it's the ENERGY of the photons that are ejecting the electrons from the metal atoms in the photoelectric effect. So in that case, light is acting as photon particles, not as waves. Also, the equation that is related to the photoelectric effect measur...

CHEMISTRY COMMUNITY

Search found 23 matches

Re: Post All Chemistry Jokes Here

Re: Saying Thank You to Dr. Lavelle

Re: Question 5 on the 2013 final

Re: Catalyst

Re: Slow Reaction

Re: Changes in both volume and temp [ENDORSED]

Re: Detail in the Rate Laws

Re: Catalyst

Re: Number of mols to use in the equation [ENDORSED]

Re: Conductor as an Electrode

Re: Derivations

Re: Chemical equilibrium

Re: Heisenberg-Hasselbach

Re: What do we do if one atom has an atomic number below 8 and the other has an atomic number above 8?

Re: What does a conjugate acid/base do? [ENDORSED]

Re: Indicators

Re: Bis

Re: Equilibrium Constants for Various Reactions

Re: Duality of the electron

Re: Common Acids and Bases

Re: Polar/nonpolar [ENDORSED]

Re: What is MO theory for? [ENDORSED]

Re: Wavelength vs. Photons [ENDORSED]