CHEMISTRY COMMUNITY

Robert Cross 1A

KSong_3C wrote:I think it’s just everything we learn after the midterm!

I think it's on everything that wasn't on the midterm that we learned before the midterm + what we learned after the midterm

Robert Cross 1A

For the current VSEPR material, I found that flashcards were helpful in learning the various molecule configurations and shapes, so I'd have to recommend those

Robert Cross 1A

I think we need to know relatively, but not the exact figure

Robert Cross 1A

Electron affinity increases as you go up and to the right of the periodic table

Robert Cross 1A

Because the bonding pairs in the double/triple bond are sharing the same region of electron density around the same two positive poles, the pairs are forced to occupy the same region of electron density.

Robert Cross 1A

Lauren Sanchez 3D wrote:So if the difference in electronegativity is greater than 2, then the bond is ionic?

Yes. An ionic bond is any bond with a delta greater than 2 between the electronegativities of the two bonding elements.

Robert Cross 1A

I'm going to ask in my discussion section this week but I'm fairly certain it's only on post-midterm topics.

Robert Cross 1A

I don't know personally, but if the CHEM14 series is a part of your major requirements, it may make sense for you to ask to meet with your departmental advisor for a half-hour, as they should have a good sense of what works better for students and what doesn't. Just my $.02

Robert Cross 1A

Electronegativity increases as you go up and to the right of the periodic table until the final Group 18 (Noble Gases). Group 18 is all the way to the right of the periodic table, except all of these have stable valence shells so their electronegativity is a much lower value than the proceeding grou...

Robert Cross 1A

The bond type doesn't necessarily contribute to boiling point, but the IMFs associated with certain bonds do. For instance, ionic salts like NaCl have strong ion-ion forces which give it its high boiling point because it requires a lot of energy in the form of heat to overcome these forces. F 2 is ...

Robert Cross 1A

Good luck everyone!!!

Robert Cross 1A

I found the syllabus goes lists every topic that is covered in each unit, which might be helpful in figuring out what will be on the midterm

Robert Cross 1A

I believe so, yes

Robert Cross 1A

Cl generally does not want to form double bonds with C because Cl has 7 valence electrons and just needs one additional bond to attain an octet

Robert Cross 1A

I looked through his website and didn't find them, but this would be a helpful review tool

Robert Cross 1A

Yes, I believe those are correct, according to what I could find on Google

Robert Cross 1A

I think it's the highest electronegativity because it is at the top right of the periodic table. Halogen's are known for being very reactive because of their valence shell being one electron away from a full octet. Although Neon is further right on the table, it is a noble gas, which are nonreactive...

Robert Cross 1A

He mentioned that in lectures although he said it is not a part of our syllabus! It is essentially bodies that absorb/emit all frequencies therefore would be essentially invisible. If you are interested in reading more into this topic, I found this simplified wikipedia article helpful in understand...

Robert Cross 1A

Simran Athwal-Dis 3A wrote:Is it true that for every double bond, there is one pi bond and for every triple bond, there are 2 pi bonds?

Yes.

Single bond = 1 sigma bond, 0 pi bonds
Double bond= 1 sigma bond, 1 pi bond
Triple bond= 1 sigma bond, 2 pi bonds

Robert Cross 1A

It means that one or more of the electrons in a molecule's bond is not strictly limited to being shared between two atoms. I see "delocalized" as meaning it is a rogue electron (i.e. it moves between the atoms more fluidly/is not strictly limited to one bonding pair of atoms). This can be ...

Robert Cross 1A

Callum Guo 1A wrote:i don't think theres a consensus about that, it's a weird property of light to have momentum but not mass. Heres an article that I read online: http://www.desy.de/user/projects/Physic ... _mass.html

Thank you so much for sharing this, I'd been wondering about this myself :)

Robert Cross 1A

For the purposes of this class I think we're best off using the value given to us on Lavelle's equation sheet

Robert Cross 1A

I agree with everything posted so far, but I think for clarification it should be noted that the work function of a particular metal is not dependent on the intensity of the light, but rather the individual energy of each photon. Essentially, an electron can only be emitted from the metal if the ene...

Robert Cross 1A

Thank you for the clarification. This is helpful :)

Robert Cross 1A

In my experience with high school chem + this course, it seems like chemistry calculations tend to be mostly done with grams. If they specifically ask you to provide an answer with another unit of mass, use that unit, but generally grams are the unit of measure used.

Robert Cross 1A

Good luck everyone!

Robert Cross 1A

Despite lacking mass, the release of a photon and its inherent energy results in a change in the magnetic field of the surrounding area. In QM, energy released by a photon is directly linked to a change in the magnetic field along the path of the ejected photon.

Robert Cross 1A

For destructive interference, would it be possible for the two waves to be equal to each other so that they cancel out or does the “negative” have to be smaller than the “positive” wave? Yes. A good real life example that helped me better conceptualize this can be found in how noise-cancelling head...

Robert Cross 1A

This article discusses how integral chemistry is to the field of art restoration

https://nuscimag.com/the-chemistry-of-art-restoration-1a034a8525c2

Robert Cross 1A

Thank you for the clarification!

Robert Cross 1A

Hello there! They are two separate things, although they are related. The percent yield is calculated by taking the mass of the actual yield (result of an experiment) divided by the mass of the theoretical yield. Then, one would multiply by 100% to express the percent yield. Basically, the percent y...

Robert Cross 1A

I was worried about this issue. Thank you so much for the fix :)

Robert Cross 1A

I find that reading the textbook can help, however normally I like to supplement reading the textbook by also looking up the concept online/reading an internet explanation/watching Khan Academy videos. I think combining resources is the most effective way to gather information on a topic, especially...

Robert Cross 1A

With regards to our fundamental and quantum understanding of electrons, I think it's important to point out a flaw that seems to have permeated throughout our education system. For me at least, I grew up being told that electrons were spherical in nature and orbited around the nucleus on set courses...

Robert Cross 1A

I've always been one to take walks as a part of my studying process. I find it can be helpful in relaxing me, especially when I've been studying for hours at a time. There have been plenty of studies which have revealed the mental and physical benefits of even just a twenty minute stroll. Walking in...

CHEMISTRY COMMUNITY

Search found 35 matches

Re: Test 2 Topics

Re: Study Tips

Re: Bond Angles

Re: electron affinity

Re: Double and triple bonds

Re: ionic character

Re: Test 2

Re: chem 14b + cehm14bl

Re: Electronegative

Re: Boiling point

Re: Midterms

Re: study guide

Re: Dipole, midterm?

Re: How to know where a double bond should go?

Re: slides

Re: Electron Configurations for Exceptions

Re: Electronegativity

Re: What is it?

Re: Sigma vs. Pi

Re: Delocalization

Re: EM Radiation and DeBroglie Equation

Re: Speed of Light

Re: The Work Function

Re: s-, p-, d- ,f- orbitals

Re: Calculate using kg or g?

Re: First Test Result

Re: EM waves

Re: Constructive & Destructive

Re: Chemistry News

Re: Wavelength Plausibility

Re: Percent or theoretical yield

Re: Book Access Issues

Re: Reading the textbook

Re: Expectations

Re: Final Jitters