Search found 50 matches
- Sun Nov 24, 2019 4:21 pm
- Forum: General Science Questions
- Topic: Review Sessions for Final
- Replies: 7
- Views: 604
Re: Review Sessions for Final
Professor Lavelle should let us know via email about review sessions and I think the UA, Lyndon Bui might also be planning a review sess as well.
- Sun Nov 24, 2019 4:21 pm
- Forum: General Science Questions
- Topic: Review Sessions for Final
- Replies: 7
- Views: 604
Re: Review Sessions for Final
Professor Lavelle should let us know via email about review sessions and I think the UA, Lyndon Bui might also be planning a review sess as well.
- Sun Nov 24, 2019 4:20 pm
- Forum: Student Social/Study Group
- Topic: Test 2 and Final
- Replies: 18
- Views: 940
Test 2 and Final
Hi, I was just wondering when we're supposed to get back Test 2 and also when and what the final will be covering? Thank you!
- Thu Nov 21, 2019 8:11 pm
- Forum: Sigma & Pi Bonds
- Topic: Coordination # and Steric #
- Replies: 2
- Views: 221
Coordination # and Steric #
Hi, I'm a bit confused if Coordination numbers and steric numbers are the same because I've looked it up on the internet and there are some resources that say they are the same while others say otherwise. Please advise, thanks!
- Tue Nov 19, 2019 9:15 pm
- Forum: General Science Questions
- Topic: Test 2
- Replies: 7
- Views: 588
Test 2
Are we going to get a sheet with all the electron shapes (Ex: tetrahedral, trigonal pyramidal) on test 2 or are we going to have to memorize them all?
- Tue Nov 19, 2019 8:47 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Difference between Electorn arrangement and VSEPR
- Replies: 1
- Views: 201
Difference between Electorn arrangement and VSEPR
Hi, does anyone know what's the difference between finding the VSEPR model vs. finding the electron configuration because I'm a little confused. Furthermore, are the shapes of tetrahedral and trigonal pyramid the same, and why are they different from one another? Thank you!
- Tue Nov 19, 2019 8:47 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Difference between Electorn arrangement and VSEPR
- Replies: 5
- Views: 457
Difference between Electorn arrangement and VSEPR
Hi, does anyone know what's the difference between finding the VSEPR model vs. finding the electron configuration because I'm a little confused. Furthermore, are the shapes of tetrahedral and trigonal pyramid the same, and why are they different from one another? Thank you!
- Wed Nov 13, 2019 3:56 pm
- Forum: SI Units, Unit Conversions
- Topic: Kg
- Replies: 4
- Views: 525
Re: Kg
FOr this class at least, I don't think we'll go into too much depth why we use kg but just know that when you're solving an equation, the values of the mass should be in kg
- Wed Nov 13, 2019 3:54 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Diatomic Molecules
- Replies: 6
- Views: 395
Re: Diatomic Molecules
Because of their differing electronegativities, the atoms will never be nonpolar because they have differnet charges.
- Wed Nov 13, 2019 3:46 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Week 9 homework
- Replies: 11
- Views: 752
Re: Week 9 homework
I think we do have homework due but most TA's are lenient and some even let you digitally scan it and send it so just shoot an email to your TA.
- Wed Nov 13, 2019 3:41 pm
- Forum: *Particle in a Box
- Topic: TEST 2
- Replies: 14
- Views: 1393
Re: TEST 2
Test 2 is during week eight and tests all materials given to us after the midterm up to probably the monday and wednesday of that week. Hope this helps!
- Wed Nov 13, 2019 3:39 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Class grading
- Replies: 12
- Views: 803
Re: Class grading
As today in class, Professor Lavelle stated he was pleased with the average of the midterm, I think its unlikely that he'll curve the class, but like the others said CHem community and homework are both good cushions
- Wed Nov 13, 2019 3:37 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Formal Charge
- Replies: 9
- Views: 830
Re: Formal Charge
I tend to do it on a separate piece of paper and by the end of it, I box the entire lewis structure and write the overall formal charge in the upper right corner of said box.
- Wed Nov 13, 2019 3:35 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Shape
- Replies: 8
- Views: 478
Re: Shape
Yes , we shouldn't be worrying about lone pairs because professor lavelle mentioned that we only need to name the molecule.
- Wed Nov 13, 2019 3:33 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: molecular shape
- Replies: 8
- Views: 545
Re: molecular shape
There are several general rules to help determine, and thus memorization is required. To determine the molecular shape, both lone pair electrons and bonding pair electrons need to be considered; professor Lavelle hasn't discussed this in lecture yet. However, to name the shape of the molecule, only...
- Wed Nov 13, 2019 3:32 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Midterm Answers
- Replies: 10
- Views: 751
Re: Midterm Answers
Matt Sanruk 4F wrote:These show detailed, step by step solutions?
Sometimes, it really depends on the type of question. For very simple questions, likely not, but for harder questions, yes most likely
- Wed Nov 13, 2019 3:31 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Ground state? [ENDORSED]
- Replies: 8
- Views: 1962
Re: Ground state? [ENDORSED]
I believe the ground state refers to the initial state, so the state without any charges and without abbreviating it. It's almost like the full state of the electorn
- Tue Oct 29, 2019 10:31 pm
- Forum: Lewis Structures
- Topic: Orbitals
- Replies: 9
- Views: 497
Re: Orbitals
Yes, because you remove the electron from the highest orbital, the s orbital would be where you remove the electron first.
- Tue Oct 29, 2019 10:29 pm
- Forum: Ionic & Covalent Bonds
- Topic: Review mesh
- Replies: 2
- Views: 232
Re: Review mesh
There probably won't be another sect purely dedicated to fundamentals, however on the midterm, there generally aren't many fundamental problems for better or for worse, because they'll be focused on the newer material. Hope this helps!
- Tue Oct 29, 2019 10:28 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Midterm
- Replies: 7
- Views: 456
Re: Midterm
Our midterm is on November 6th however, the locations of said midterm have yet to be disclosed
- Tue Oct 29, 2019 10:26 pm
- Forum: General Science Questions
- Topic: Midterm 1
- Replies: 2
- Views: 338
Re: Midterm 1
Midterm 1 will cover fundamentals, quantum and a little bit of chemical bonds
- Tue Oct 29, 2019 10:25 pm
- Forum: Ionic & Covalent Bonds
- Topic: Midterm
- Replies: 10
- Views: 535
Re: Midterm
Not to worry, the only thing necessary for Professor Lavelle's midterms are pens/pencils, a calculator and your bruin ID
- Thu Oct 24, 2019 6:37 pm
- Forum: Properties of Electrons
- Topic: hw
- Replies: 6
- Views: 383
Re: hw
The questions from this week should be from quantum, but i recommend you put chemical bonds in your homework just so you can get the practice in.
- Thu Oct 24, 2019 6:36 pm
- Forum: Balancing Chemical Reactions
- Topic: Balancing equations.
- Replies: 35
- Views: 2884
Re: Balancing equations.
Generally, when balancing equations, the general rule is that the number of elements on one side should be exact to the number of elements on the other side, so if one element has even one more than the other side, that means you have to rethink the question. Hope this helps!
- Thu Oct 24, 2019 6:34 pm
- Forum: Lewis Structures
- Topic: Where to start putting dots for electrons
- Replies: 10
- Views: 594
Re: Where to start putting dots for electrons
There aren't any rules as to where to start putting electrons, however there are rules once we start learning about formal charge on what's the most ideal configuration of certain electrons to attain neutral charge, but don't worry about that for now.
- Thu Oct 24, 2019 6:33 pm
- Forum: Ionic & Covalent Bonds
- Topic: Does the Octet Rule apply to Boron?
- Replies: 14
- Views: 888
Re: Does the Octet Rule apply to Boron?
Unlike the other elements, boron is not one of the elements subject to the octet rule as it is more stable when it has 6 electrons rather than eight.
- Sun Oct 20, 2019 1:33 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Writing Electron Configurations
- Replies: 7
- Views: 361
Re: Writing Electron Configurations
you don't need to write x, y, or z next to your electron configurations. I think Dr. Lavelle just put that in lecture as extra information but for now dont' worry about it.
- Sun Oct 20, 2019 1:30 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Short Hand
- Replies: 11
- Views: 461
Re: Short Hand
ONce you get the base configuration, usually you don't want to have the long electron configuration, so we use the elements in the far-right column of the periodic table (starting with Helium and ending with Radon) for short-hand. Basically once you have the electron configuration, in the event that...
- Sun Oct 20, 2019 1:24 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Electron Configuration
- Replies: 1
- Views: 140
Re: Electron Configuration
Basically when it comes to electron configuration, we want to think of s, p, d, and f which can all hold a certain amount of electrons in them. If you reference our textbook (page 33) each orbital (s, p, d, f) has an L or "orbital angular momentum quantum number" so for each s, p, d, and f...
- Sun Oct 20, 2019 1:11 pm
- Forum: Administrative Questions and Class Announcements
- Topic: UA Session and Step-Up Program
- Replies: 4
- Views: 260
Re: UA Session and Step-Up Program
The UA sessions and Step-up programs are very helpful as you get more one on one help rather than being in a massive class setting. I would also recommend going to O.H. of T.A.'s because they can be very helpful as they're grad students. If you're struggling with a specific topic though, the session...
- Sun Oct 20, 2019 1:08 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Ordering of s and d orbitals
- Replies: 2
- Views: 110
Re: Ordering of s and d orbitals
Generally, in this class we should put the d before the s, also because you can get deducted points in special cases where one orbital steals an electron from another (ex: 3d^2 4d^9 -> 3d^1 4 d^10). Hope this helps :)
- Sun Oct 20, 2019 1:06 pm
- Forum: *Black Body Radiation
- Topic: Wein's Law
- Replies: 5
- Views: 591
Re: Wein's Law
I don't think we need to know Wein's law. If we need to know a value, it'll be put on the equations sheet (where all the formulas, and values are put).
- Sun Oct 20, 2019 1:05 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: writing electron configurations
- Replies: 4
- Views: 212
Re: writing electron configurations
I never did electron configurations in high school and I am super lost. In my notes I have that for carbon when there are 6 electrons, the configuration is 1s² 2s² 2px 2py. Could someone please explain to me where these numbers came from? To add to what the people are saying above, when I was initi...
- Sun Jul 14, 2019 7:28 pm
- Forum: Photoelectric Effect
- Topic: Which Equation Do I Use?
- Replies: 4
- Views: 931
Re: Which Equation Do I Use?
You should choose which equation to use based on what kind of energy it's asking for. Technically both equations are the same but you can substitute E(k) with 1/2mv^2. The discerning factor is what are the givens in the problem and what the problem asks for.
- Sun Jul 14, 2019 7:18 pm
- Forum: General Science Questions
- Topic: Different forms of Energy
- Replies: 3
- Views: 686
Re: Different forms of Energy
Depends on how much detail you want to go into, but if we're speaking broadly, the two main categories are kinetic energy and potential energy. Kinetic energy is the energy that is released in movement, so if you're walking you're releasing kinetic energy. On the other hand, potential energy, as the...
- Sun Jul 14, 2019 7:14 pm
- Forum: Lewis Structures
- Topic: Drawing lewis structures
- Replies: 5
- Views: 684
Re: Drawing lewis structures
Basically you should draw it like how you would any normal lewis structure but depending if it has a negative charge or positive charge you remove or add molecules, so for negatively charged you add and vice-versa
- Sun Jul 14, 2019 7:02 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Formal Charge
- Replies: 12
- Views: 1301
Re: Formal Charge
I wouldn't say you need to show all your work, but I definitely recommend it, in the worst case hypothetical you get the question wrong, you can, at the very least, get partial credit for showing your work.
- Sun Jul 14, 2019 5:03 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Subshells
- Replies: 2
- Views: 510
Re: Subshells
According to the TA, a subshell is a specific s or p, so how l can equal 0, 1, 2, or 3, while a shell is a principal quantum #, represented by n
- Sun Jul 14, 2019 5:00 pm
- Forum: Student Social/Study Group
- Topic: Study Group
- Replies: 2
- Views: 607
Re: Study Group
Hi, i'm a bit late for the midterm but i'm open to study for the final if you're down
- Sun Jul 14, 2019 4:57 pm
- Forum: Photoelectric Effect
- Topic: Converting electron volts? [ENDORSED]
- Replies: 2
- Views: 632
Re: Converting electron volts? [ENDORSED]
If you look at the constants and equations sheet, you can see the convertion factor from eV (volts) to J whcih is for 1 eV there are 1.602x10^-19 J
- Sun Jul 14, 2019 4:56 pm
- Forum: Photoelectric Effect
- Topic: Homework Problems
- Replies: 2
- Views: 471
Re: Homework Problems
First use the De Broglie equation as appropriate turning (lambda) = h/p into (lambda)= h/mv. Next convert the mass of an electron using your conversions, so here are 1000 g in one kg. Once converted you should be left with 9.10939x10^-31. Afterwards convert km into meters so that you're also using t...
- Sun Jul 14, 2019 4:41 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Electron configuration
- Replies: 3
- Views: 679
Re: Electron configuration
No, you would have to write out Ca as a ground configuration initially and then at the very end with your final electron configuration, remove two electrons as appropriate for Ca^2+
- Sun Jul 14, 2019 4:40 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: Test 1 number 7
- Replies: 4
- Views: 2699
Re: Test 1 number 7
The equation was for molarity which is M (molarity) = (moles)/(liters). If you have different measurements like mg you need to convert, so for question seven you needed to plug in the values after converting mg to liters.
- Sun Jul 14, 2019 4:38 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Electron Configuration for 1st row transition metals
- Replies: 6
- Views: 1123
Re: Electron Configuration for 1st row transition metals
Cu and Cr are both special cases and the only special cases in that row. Basically, because Cu's configuration is 3d^9 and 4s^2, the 3d^9 steals an electron from 4s^2 turning it into 4d^10 and the same thing with Cr.
- Sun Jul 14, 2019 4:36 pm
- Forum: Ionic & Covalent Bonds
- Topic: Homework 3.5
- Replies: 7
- Views: 1085
Re: Homework 3.5
Personally, I have a hardtime doing electron configuration the way the professor teaches us, so I watched this video and it helped make electron configuration easier especially with elements like Bi
https://www.youtube.com/watch?v=2AFPfg0Como
https://www.youtube.com/watch?v=2AFPfg0Como
- Sun Jul 14, 2019 4:31 pm
- Forum: Ionic & Covalent Bonds
- Topic: Friday's Lecture July 12, 2019
- Replies: 2
- Views: 491
Re: Friday's Lecture July 12, 2019
I think it's a matter of when the atom is most stable, so we know ideally that an atom would like to fulfill the octet rule, using double bonds, single bonds, etc. or lone atom pairs but it's just a matter of when B is the central element, it will want to be as stable as possible.
- Sun Jul 14, 2019 4:25 pm
- Forum: Ionic & Covalent Bonds
- Topic: Ground State
- Replies: 13
- Views: 1475
Re: Ground State
Actually the configuration for Cu is [Ar}3d^9 4s^2 but because 3d^9 is so close to have a complete shell it steals an electron from 4s^2 taking away one electron and reducing it to [Ar]3d^10 4s^1. Lastly because Cu^+ has the plus sign it means you're removing an electron versus in the hypothetical i...
- Sun Jul 14, 2019 4:22 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Which do you prioritize first
- Replies: 10
- Views: 1210
Re: Which do you prioritize first
I prioritize valence electrons personally, because without the valence electrons, you can't calculate the formal charge technically
- Sun Jul 07, 2019 12:09 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Atomic Orbitals [ENDORSED]
- Replies: 5
- Views: 886
Re: Atomic Orbitals [ENDORSED]
I don't think so, but I think we do need to know the different types of orbitals like s, p, d and f.
- Sun Jul 07, 2019 12:08 pm
- Forum: Photoelectric Effect
- Topic: Photo electric effect
- Replies: 7
- Views: 924
Re: Photo electric effect
Vacuum is basically just referring to an enclosed sapce, so for example space is also a vacuum. We need a vacuum though because without it, the experiment will have other external forces interfering like the presence of air molecules. Because the photo electric effect centers on the idea of electron...