Search found 106 matches
- Mon Mar 15, 2021 12:07 pm
- Forum: Student Social/Study Group
- Topic: How are y'all doing?
- Replies: 46
- Views: 2968
Re: How are y'all doing?
I am really happy the chemistry final is over with. I have two more and then I'll be finished, so I'm still stressed out and ready to be done with this quarter. Even though I made sure to get ahead of the chemistry (last quarter I fell way behind), I still think I could have done a better job at tim...
- Sun Mar 14, 2021 6:18 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Final Grades
- Replies: 19
- Views: 1686
Re: Final Grades
Since our final was today, I would say maximum a week or so? Same as midterm and the previous final as well.
- Sun Mar 14, 2021 2:46 pm
- Forum: General Science Questions
- Topic: No Lavelle Chem 14C?
- Replies: 68
- Views: 5946
Re: No Lavelle Chem 14C?
Lavelle doesn't teach Chem 14C sadly :(
- Sun Mar 14, 2021 2:44 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Saying Thank You to Dr. Lavelle
- Replies: 490
- Views: 619098
Re: Saying Thank You to Dr. Lavelle
Dr Lavelle, Thank you so much for being a kind, supportive, and caring professor for this accelerated introductory course. You care so much about your students, and that shows with your consistency in hourly lectures, Chemistry Community, daily review sessions, etc. You truly want your students to s...
- Sun Mar 14, 2021 10:48 am
- Forum: Biological Examples
- Topic: Do we need to know this
- Replies: 3
- Views: 721
Re: Do we need to know this
I would go over simple examples, like the ones he talked about during his lecture on kinetics. I don't think the final is going to go way in depth on the biology.
- Sun Mar 14, 2021 10:44 am
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Effect of catalyst
- Replies: 22
- Views: 2501
Re: Effect of catalyst
The uncatalyzed reaction proceeds via a one-step mechanism (one transition state observed), whereas the catalyzed reaction follows a two-step mechanism (two transition states observed) with a notably lesser activation energy. Enthalpy is a state function, so we are only focusing on final minus initi...
- Thu Mar 11, 2021 11:53 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Bomb Calorimeter
- Replies: 17
- Views: 932
Re: Bomb Calorimeter
Bomb calorimeters are sealed and insulated, so it can be assumed that they're all isolated systems.
- Thu Mar 11, 2021 11:52 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: q and w for an Isolated System
- Replies: 19
- Views: 3500
Re: q and w for an Isolated System
delta U, q, and w are all equal to 0 for an isolated system since there is no energy transfer between the system and the surroundings
- Thu Mar 11, 2021 11:51 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Units for Activation Energy
- Replies: 28
- Views: 2072
Re: Units for Activation Energy
kilojoules per mole or joules per mole are the appropriate units for activation energy
- Thu Mar 11, 2021 11:48 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: What was your favorite chem topic?
- Replies: 137
- Views: 13047
Re: What was your favorite chem topic?
Chemical equilibrium, periodic table trends / atomic configuration, kinetics!!
- Thu Mar 11, 2021 11:47 pm
- Forum: Administrative Questions and Class Announcements
- Topic: [CHEM 14B KARAOKE]
- Replies: 68
- Views: 7103
Re: [CHEM 14B KARAOKE]
I joined and ended up having a blast!! Thank you so much for something so lighthearted in a moderately stressful class
- Thu Mar 11, 2021 11:45 pm
- Forum: Student Social/Study Group
- Topic: How are y'all doing?
- Replies: 46
- Views: 2968
Re: How are y'all doing?
Burnt out. Feel like I am constantly running out of time. Other than that ... excited for spring break :))
- Thu Mar 04, 2021 1:45 pm
- Forum: Student Social/Study Group
- Topic: Fave movie/show
- Replies: 67
- Views: 5561
Re: Fave movie/show
Breaking Bad, How to Get Away With Murder, Orange is the New Black are some of my all time favorites
- Thu Mar 04, 2021 1:43 pm
- Forum: Student Social/Study Group
- Topic: What do you miss / What are you looking forward to?
- Replies: 92
- Views: 12493
Re: What do you miss / What are you looking forward to?
I'm a freshman and I am looking forward to talking and meeting new people :) I'm excited for dorm life (if that ever happens), finding cute secluded study spots on campus, coffee shops, cafes, etc. I can't wait to workout at the UCLA gym and attend my classes in person. Just a few out of so many thi...
- Wed Feb 24, 2021 1:36 am
- Forum: Student Social/Study Group
- Topic: Power Outages
- Replies: 7
- Views: 500
Re: Power Outages
Even Socal is experiencing unwarranted power outages :/ I would just try to communicate with your professors before if you can, or provide an explanation afterwards to accommodate for makeups. Wishing you good luck!!!
- Wed Feb 24, 2021 1:33 am
- Forum: Student Social/Study Group
- Topic: Work and school
- Replies: 16
- Views: 987
Re: Work and school
I struggle with this as well. With balancing work for 20-25 hours a week, to spending time with my family, friends, and s/o, as well as attending all of the lectures and completing homework on time is extremely difficult and I'd be lying if I told you I had it all figured out (lol its 1:30 am). My b...
- Wed Feb 24, 2021 1:29 am
- Forum: Administrative Questions and Class Announcements
- Topic: Chemistry Community Deadlines
- Replies: 11
- Views: 1101
Re: Chemistry Community Deadlines
The post will count for Week 7. The cutoff is Sunday 11:59 pm!
- Tue Feb 23, 2021 11:07 am
- Forum: Student Social/Study Group
- Topic: Fave food
- Replies: 266
- Views: 47010
Re: Fave food
I love salt and vinegar chips. Sushi will always be my favorite food. Banana bread, mint chocolate chip icecream, smoothies, jasmine boba. All are some of my favorite snacks and foods :)
- Tue Feb 23, 2021 11:05 am
- Forum: Administrative Questions and Class Announcements
- Topic: Can We Review our Exams?
- Replies: 69
- Views: 3933
Re: Can We Review our Exams?
You can't review it on your own, but if you go to a scheduled TA office hours they can verbally tell you which ones you got wrong and the correct answer!
- Thu Feb 18, 2021 8:26 am
- Forum: Administrative Questions and Class Announcements
- Topic: Midterm 2 and Final
- Replies: 25
- Views: 1373
Re: Midterm 2 and Final
Based on Chem 14A, all exams are proctored very similarly and have the same protocol. TA discussion group with camera pointed to your hands, test on Respondus lockdown broswser.
- Thu Feb 18, 2021 8:25 am
- Forum: Student Social/Study Group
- Topic: Classes for next quarter?
- Replies: 165
- Views: 19657
Re: Classes for next quarter?
As a response to my own post, I am taking LS7A, Ling 1, and Engcomp 3D. Not even close to my ideal schedule, but with my morning pass and UCLA's lack of uploading enough classes for all students - this will have to do. Linguistics fills a GE and the Engcomp fills the Writing I requirement. I wanted ...
- Tue Feb 16, 2021 9:25 am
- Forum: Administrative Questions and Class Announcements
- Topic: MyUCLA Grade
- Replies: 27
- Views: 1663
Re: MyUCLA Grade
I wouldn't worry too much! As of right now, I can see all of my previous grades, but I think there's nothing wrong. I would check again though
- Tue Feb 16, 2021 9:18 am
- Forum: Ideal Gases
- Topic: Chem BL
- Replies: 107
- Views: 10119
Re: Chem BL
I am planning to take BL separate from Chem C, and I had a lot of difficulty with closed classed or final overlap.
- Wed Feb 10, 2021 1:49 pm
- Forum: Student Social/Study Group
- Topic: Week 6
- Replies: 5
- Views: 367
Re: Week 6
I watch lectures on 1.25 or 1.5 speed, and while Lavelle is going through a slide, I try to understand what he's saying. After he's done, I copy that slide down with some additional notes and continue that for the rest of his lecture. It can be time consuming, but I think it helps you grasp the mate...
- Wed Feb 10, 2021 1:46 pm
- Forum: Student Social/Study Group
- Topic: Classes for next quarter?
- Replies: 165
- Views: 19657
Classes for next quarter?
What classes are you guys enrolling in for Spring quarter?
- Wed Feb 10, 2021 1:44 pm
- Forum: Student Social/Study Group
- Topic: Students Who Have a Job
- Replies: 103
- Views: 12689
Re: Students Who Have a Job
This really resonates with me. I work two jobs back to back right after my classes, and come home most days at 10 pm when I finish. I also try to make time to hang out with my boyfriend and my best friend and my family, and up until last week I was managing, but now I have a huge pile of workload th...
- Wed Feb 10, 2021 1:39 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Can We Review our Exams?
- Replies: 69
- Views: 3933
Re: Can We Review our Exams?
In Chem 14A, TA's would offer office hours to tell you which problems you got wrong. They don't show the question, but they explain the right answer
- Wed Feb 03, 2021 4:33 pm
- Forum: Student Social/Study Group
- Topic: Shoutout to Dr. Lavelle
- Replies: 8
- Views: 588
Re: Shoutout to Dr. Lavelle
Thank you Dr. Lavelle! So many support systems along with chemistry community to help answer questions when feeling lost.
- Wed Feb 03, 2021 4:32 pm
- Forum: General Science Questions
- Topic: Midterm 1 Reactions
- Replies: 70
- Views: 5812
Re: Midterm 1 Reactions
I feel like the content was more or less expected. Some questions were worded a bit weird, and it took me a little bit to understand what was being asked of me. I did rush the last three questions, but I don't feel super defeated post midterm.
- Wed Feb 03, 2021 4:30 pm
- Forum: Phase Changes & Related Calculations
- Topic: midterm respondus
- Replies: 19
- Views: 881
Re: midterm respondus
Once you download it through CCLE, it should open up automatically!
- Wed Feb 03, 2021 4:29 pm
- Forum: Student Social/Study Group
- Topic: Best study methods
- Replies: 9
- Views: 504
Re: Best study methods
I prefer watching the lectures as he posts them (not falling super behind) as well as keeping up with the Sapling. Reading the textbook is also super helpful because it clarifies ideas that sometimes the lectures don't go into. I don't always do the textbook problems, but they do show up on the exam...
- Wed Feb 03, 2021 4:26 pm
- Forum: General Science Questions
- Topic: Midterm
- Replies: 10
- Views: 443
Re: Midterm
He sent an email saying that they would be out by tonight!
- Wed Feb 03, 2021 4:24 pm
- Forum: Administrative Questions and Class Announcements
- Topic: HW Due Date
- Replies: 15
- Views: 756
Re: HW Due Date
Now moved to the end of Week 5!
- Mon Feb 01, 2021 9:15 am
- Forum: Student Social/Study Group
- Topic: Go treat yourself after MT1!
- Replies: 75
- Views: 6469
Re: Go treat yourself after MT1!
I went thrifting and then I had a sleepover with my best friend :) We went to go get some bomb sushi, made chocolate covered strawberries, listened to good music, and just had a good time. Love the positivity
- Mon Feb 01, 2021 9:11 am
- Forum: General Science Questions
- Topic: Studying
- Replies: 67
- Views: 4224
Re: Studying
Watch lectures on time when they're posted. Understand Sapling. Textbook problems when you can. Reading the textbook is also very helpful to me. I never attend office hours but they seem to be helpful too.
- Mon Feb 01, 2021 9:10 am
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Hess's Law
- Replies: 58
- Views: 3323
Re: Hess's Law
Hess's Law of Constant Heat Summation states that regardless of the multiple stages or steps of a reaction, the total enthalpy change for the reaction is the sum of all changes. This law is a manifestation that enthalpy is a state function.
- Mon Feb 01, 2021 9:07 am
- Forum: Student Social/Study Group
- Topic: Work Life Balance
- Replies: 44
- Views: 2010
Re: Work Life Balance
I think the balance between work, school, and social interactions is very very difficult to manage. I am definitely not the representation of a perfect balance, but I normally try to watch the lectures the day Lavelle posts them (and for all my other classes to stay on top of lectures and go to ever...
- Mon Feb 01, 2021 9:03 am
- Forum: General Science Questions
- Topic: Midterm 1 Reactions
- Replies: 70
- Views: 5812
Re: Midterm 1 Reactions
I think it was more tedious and I felt like I was running out of time by the end of the test. I know it would've been better if I had done all of the textbook problems, but I didn't get to all. Overall, Lavelle and the textbook did a good job in preparing me.
- Mon Jan 25, 2021 9:37 am
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Rounding E Values in ICE charts
- Replies: 17
- Views: 742
Re: Rounding E Values in ICE charts
If the K value is less than 1.0 x 10^-3, then the x can be dropped. Lavelle prefers we drop it at 1.0 x 10^-4 to be more safe, but essentially its when the K value is so small it doesn't affect the overall concentration.
- Mon Jan 25, 2021 9:32 am
- Forum: Student Social/Study Group
- Topic: Favorite Music
- Replies: 113
- Views: 14586
Re: Favorite Music
I've been super all over the place lately. Kanye West, The Weeknd, Kid Cudi, Tyler the Creator, Lana del Rey, Frank Ocean, PATD, Fall Out Boy. Anything that hits in that specific moment in time.
- Mon Jan 25, 2021 9:30 am
- Forum: Student Social/Study Group
- Topic: Comfort Movies
- Replies: 168
- Views: 36714
Re: Comfort Movies
Any Disney classic. The Parent Trap is a great movie. CAMP ROCK! These immediately take me back.
- Mon Jan 25, 2021 9:27 am
- Forum: Student Social/Study Group
- Topic: Exam Duration
- Replies: 7
- Views: 346
Re: Exam Duration
Same as last quarter, the TAs would probably want us to join 5-10 minutes early to set up, check papers, and get everybody situated. Then, once you open up Respondus and click the timer, the 50 minutes is the time limit in which you can take the test.
- Mon Jan 25, 2021 9:25 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: When to use ICE box
- Replies: 23
- Views: 996
Re: When to use ICE box
The ICE box is used to find unknown concentrations at equilibrium or initial given the concentration of one of the reactants or products.
- Tue Jan 12, 2021 12:51 pm
- Forum: Student Social/Study Group
- Topic: New Year Resolutions?
- Replies: 54
- Views: 3432
Re: New Year Resolutions?
Be more easy on myself. That being said, try to wakeup early everyday. Stay on top of my lectures, zoom calls. Maintain my time a bit better with a planner. Bike at least four times a week. Work hard, play hard :)
- Tue Jan 12, 2021 12:47 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Left vs. Right
- Replies: 29
- Views: 1158
Re: Left vs. Right
These both can be used interchangeably! It is important to note that no reaction actually "shifts". According to Le Chatelier, the position of equilibrium will move in such a way as to counteract the change.
- Tue Jan 12, 2021 12:41 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Week 1 Assignment
- Replies: 17
- Views: 796
Re: Week 1 Assignment
Sapling homework is mandatory. So the week 1 assignment for sapling is DUE the Sunday of week 2. All of the problems from the textbook are optional, and normally are extra practice plus they commonly show up on midterms and final exams.
- Tue Jan 12, 2021 12:38 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Sapling Homework
- Replies: 7
- Views: 486
Re: Sapling Homework
Make sure to log in to Sapling through CCLE. Once you're there, click "use credit" and then it should work.
- Tue Jan 12, 2021 12:32 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Getting two positive x values when using quadratic
- Replies: 43
- Views: 5053
Re: Getting two positive x values when using quadratic
I've run into this problem when completing the Sapling, but even though they are both positive, both shouldn't make sense in the context of the problem. Some people above have noticed that the correct x value is commonly the smaller one. To be sure, though, it is necessary to check for yourself.
- Tue Jan 12, 2021 12:29 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Q and K relationship
- Replies: 12
- Views: 629
Re: Q and K relationship
It is also important to note this relationship between Q and K. Q is a quantity that changes as a reaction system approaches equilibrium. K is the numerical value of Q at the "end" of the reaction, when equilibrium is reached. If Q is less than K the reaction will shift right If Q is great...
- Tue Jan 12, 2021 12:24 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Clarification of terminology
- Replies: 15
- Views: 732
Re: Clarification of terminology
All these phrases mean the same thing. You have to take into consideration too that nothing in the chemical reaction is actually "shifting", that is just simply the terminology.
- Thu Jan 07, 2021 7:12 pm
- Forum: Student Social/Study Group
- Topic: Advice for someone who didn't take 14A with professor Lavelle
- Replies: 61
- Views: 3419
Re: Advice for someone who didn't take 14A with professor Lavelle
In my opinion, watching lectures on the day they come out is the way to go. At one point, I was behind on fourteen lectures for a midterm, and it is almost impossible cramming that much. Asynchronous classes make it very easy to procrastinate, but promise me it will be way easier to follow along as ...
- Thu Jan 07, 2021 7:09 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Gas Constant (R)
- Replies: 12
- Views: 407
Re: Gas Constant (R)
In this class, R is 8.314 J·K^-1·mol^-1. It can be found on the formula sheet on Lavelle's website.
- Thu Jan 07, 2021 7:07 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Lecture Format
- Replies: 22
- Views: 953
Re: Lecture Format
Lavelle lectures are pre-recorded and posted on their assigned date (every other day of the week). You must keep yourself accountable to watch these. Discussion sections are optional, but they are helpful as you can ask any question you need. Sapling is mandatory homework you are graded on. Hope thi...
- Thu Jan 07, 2021 7:04 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Sapling Assignments
- Replies: 30
- Views: 2072
Re: Sapling Assignments
Sapling is mandatory homework, due dates are posted on there too. Textbook problems are optional and given as additional help if needed (they show up on exams sometimes)
- Thu Dec 03, 2020 1:30 pm
- Forum: Ionic & Covalent Bonds
- Topic: Polar and Nonpolar
- Replies: 37
- Views: 1981
Re: Polar and Nonpolar
It becomes way easier when you draw the molecule and draw out the vectors to signify the dipoles! If they cancel out, the molecule is nonpolar.
- Thu Dec 03, 2020 1:26 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Best Formal Charge Equations
- Replies: 24
- Views: 1168
Re: Best Formal Charge Equations
FC = valence electrons - number of dots - number of bonds/lines.
- Thu Dec 03, 2020 1:25 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bond Angles
- Replies: 13
- Views: 1578
Re: Bond Angles
First step is to draw the Lewis diagram to visualize the atom. Bond angle is determined by examining the number of lone pair electrons. This is because there is election repulsion, causing the bond angles to be slightly smaller. And as Lavelle said, we don't have to memorize these changes in angles,...
- Thu Dec 03, 2020 1:19 pm
- Forum: General Science Questions
- Topic: # of chem posts
- Replies: 27
- Views: 1994
Re: # of chem posts
December 6 - 45
December 13 - 50 posts total
December 13 - 50 posts total
- Thu Dec 03, 2020 12:36 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: polar v nonpolar molecules
- Replies: 30
- Views: 2640
Re: polar v nonpolar molecules
Polar molecules occur when there is an electronegativity difference between the bonded atoms, whereas nonpolar molecules occur when electrons are shared equal between atoms of a diatomic molecule or when polar bonds in a larger molecule cancel each other out.
- Thu Dec 03, 2020 12:34 pm
- Forum: Hybridization
- Topic: Pi Bonds Cannot Rotate
- Replies: 29
- Views: 4293
Re: Pi Bonds Cannot Rotate
Rotation around a single bond occurs readily, while rotation around a double bond is restricted. The pi bond prevents rotation because of the electron overlap both above and below the plane of the atoms.
- Thu Dec 03, 2020 12:31 pm
- Forum: Administrative Questions and Class Announcements
- Topic: 14B vs 14A
- Replies: 12
- Views: 764
Re: 14B vs 14A
I believe that it will be mostly the same. We will continue to use Sapling. I think the textbook we bought was for both classes, so just an continuation.
- Thu Dec 03, 2020 12:29 pm
- Forum: Naming
- Topic: Oxidation State
- Replies: 4
- Views: 294
Re: Oxidation State
An oxidation state is the total number of electrons that an atom either gains or loses in order to form a chemical bond with another atom. :)
- Thu Dec 03, 2020 12:23 pm
- Forum: Student Social/Study Group
- Topic: How are you?
- Replies: 154
- Views: 17038
Re: How are you?
Honestly, overwhelmed. On top of UCLA classes, I am working a job that I go to right after I finish my classes. I close almost everyday, so I come home at 10:30. I just always feel like I have absolutely no time for anything, and December is one of those months that keep me up all night. Scared for ...
- Sun Nov 29, 2020 10:03 pm
- Forum: Significant Figures
- Topic: 40. versus 40
- Replies: 23
- Views: 1761
Re: 40. versus 40
40. has 2 sig figs while 40 only has one! All above answers are correct :)
- Sun Nov 29, 2020 10:02 pm
- Forum: Ideal Gases
- Topic: Reading the textbook
- Replies: 262
- Views: 155709
Re: Reading the textbook
I think the textbook is extremely helpful in clearing up topics that weren't clearly defined in lectures. Plus, lectures are super long and have a ton of information, while the book condenses it. It is way easier to follow in my opinion!
- Sun Nov 29, 2020 10:00 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Determining Molecular Shape
- Replies: 9
- Views: 508
Re: Determining Molecular Shape
The type of bond doesn't affect molecular geometry. However, it might change the angle between the elements (as double bonds are tighter etc), but when asked, we don't take this into account. You can think about it that way conceptually, but it doesn't change the actual answer!
- Sun Nov 29, 2020 9:56 pm
- Forum: Lewis Structures
- Topic: Tips on drawing Lewis structures
- Replies: 21
- Views: 2358
Re: Tips on drawing Lewis structures
Best advice is to count the electrons first in order to fill the octets for all the atoms (as they are most stable that way).
- Sun Nov 29, 2020 9:53 pm
- Forum: Student Social/Study Group
- Topic: Week 8/9 Thoughts/Worries
- Replies: 66
- Views: 4486
Re: Week 8/9 Thoughts/Worries
I feel relatively okay in this class - tons of resources, great textbook, descriptive videos. The only issue with me is that I constantly fall behind on lectures and have to do a ton of catching up. First midterm was good, but my second I didn't perform my best. So I am a little anxious about the fi...
- Sat Nov 28, 2020 2:59 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Sapling Wk8 Q. 18, Determining Molecular Shape
- Replies: 10
- Views: 542
Re: Sapling Wk8 Q. 18, Determining Molecular Shape
Molecules are read left to right to be given the order!
- Sat Nov 28, 2020 2:59 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Sapling Wk8 Q. 18, Determining Molecular Shape
- Replies: 10
- Views: 542
Re: Sapling Wk8 Q. 18, Determining Molecular Shape
Molecules are read left to right to be given the order!
- Sat Nov 28, 2020 2:57 pm
- Forum: Polarisability of Anions, The Polarizing Power of Cations
- Topic: Polar vs. nonpolar bonds/molecules
- Replies: 8
- Views: 550
Re: Polar vs. nonpolar bonds/molecules
A bond is polar because two atoms have different electronegativities. However, when these two atoms (or more) are symmetric and have zero lone pairs, this indicates that this molecule has linear geometry. The bonds are symmetric, so their dipoles cancel out. Thus, the molecule is nonpolar. On the ot...
- Mon Nov 23, 2020 12:51 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: bond angle tips
- Replies: 10
- Views: 745
Re: bond angle tips
Best bet is to memorize them. We will continue to draw molecules and will have to know what they look like to look at its chemical properties. Luckily, its not that much and is typically straightforward once you get the hang of it.
- Mon Nov 23, 2020 12:49 pm
- Forum: Ionic & Covalent Bonds
- Topic: Polar Bonds [ENDORSED]
- Replies: 26
- Views: 1400
Re: Polar Bonds [ENDORSED]
I look at electronegativity and the presence of lone pairs in the Lewis structure. It is extremely helpful to also draw the atom and indicate all the lone pairs. If the molecule is asymmetrical with bonding, electrons, etc, then it is always non-polar because that means that one side is slightly mor...
- Mon Nov 23, 2020 12:45 pm
- Forum: Lewis Structures
- Topic: Dot stucture
- Replies: 11
- Views: 597
Re: Dot stucture
Counting the valence electrons is the first step, make sure to account for the cations/anions. Next, I write the most electronegative atom in the middle and draw bonds to make sure it has an octet (or lone pairs). I tend to use trial and error, but after practice you know how to draw basic atoms and...
- Mon Nov 23, 2020 12:42 pm
- Forum: Student Social/Study Group
- Topic: Studying From Home
- Replies: 91
- Views: 8619
Re: Studying From Home
I have the same struggle, especially this quarter. I make sure to use an agenda, because I find satisfaction in crossing of assignments that I have completed. I also try to make sure my work environment is clean (as well as my room). Sometimes I facetime my friends and we both do homework at the sam...
- Mon Nov 16, 2020 9:02 am
- Forum: Ionic & Covalent Bonds
- Topic: London Dispersion Forces
- Replies: 11
- Views: 1747
Re: London Dispersion Forces
The London dispersion force is the weakest intermolecular force. The London dispersion force is a temporary attractive force that results when the electrons in two atoms occupy positions that make the atoms form temporary dipoles.
- Sun Nov 15, 2020 9:40 am
- Forum: Resonance Structures
- Topic: Formal Charge influence on Resonance Structure
- Replies: 4
- Views: 214
Re: Formal Charge influence on Resonance Structure
The formal charge of an atom in a molecule is the hypothetical charge the atom would have if we could redistribute the electrons in the bonds evenly between the atoms. The smallest formal charge is most favorable because it is considered to be the most stable.
- Sun Nov 15, 2020 9:33 am
- Forum: Lewis Structures
- Topic: Drawing Lewis Structures on Midterm
- Replies: 31
- Views: 1335
Re: Drawing Lewis Structures on Midterm
Instructions should be clear, but if not, least formal charge is the way to go. It is the most accurate, but I'd make sure to recognize multiple structures in case.
- Sun Nov 15, 2020 9:23 am
- Forum: Student Social/Study Group
- Topic: Exercising Our Minds and Bodies
- Replies: 120
- Views: 26775
Re: Exercising Our Minds and Bodies
I go biking on my free time around my neighborhood when I can. Sometimes, I go on the trampoline or just take a walk. All of these help me clear my mind and relax a little bit
- Sun Nov 15, 2020 9:21 am
- Forum: Student Social/Study Group
- Topic: grade worries
- Replies: 119
- Views: 23809
Re: grade worries
Yes, I am always super anxious about my grades, and sometimes I feel super disconnected from UCLA so it gets hard to learn. These past few weeks have been back to back midterms so I haven't had as much time to study as for the first midterm, which means cramming for me til Tuesday morning. But just ...
- Fri Nov 06, 2020 8:50 am
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: 4s before 3d Orbital
- Replies: 11
- Views: 557
Re: 4s before 3d Orbital
The energy levels that are lowest are filled up first. Based on experimental data, it was found that the 4S shell has less energy than the 3D shell, so that's why it is filled up first. So, when writing out the electron configuration, you must keep this in mind or you will get the answer incorrect.
- Fri Nov 06, 2020 8:47 am
- Forum: Bond Lengths & Energies
- Topic: Radicals
- Replies: 5
- Views: 507
Re: Radicals
A radical is a molecule that contains at least one unpaired electron. In organic chemistry, it is more specified that radical stability increases in the order methyl < primary < secondary < tertiary, but I'm not sure how much of this we actually need to know. The stability of radicals on the carbon ...
- Fri Nov 06, 2020 8:40 am
- Forum: Ionic & Covalent Bonds
- Topic: Coulombs equation
- Replies: 4
- Views: 342
Re: Coulombs equation
Coulomb's law describes the force between two charged particles. This Coulomb force is extremely basic, since most charges are due to point-like particles. It is responsible for all electrostatic effects and underlies most macroscopic forces. This equation is given by F(e)=(kQ1Q2)/r^2 (unit in Newto...
- Fri Nov 06, 2020 8:34 am
- Forum: Student Social/Study Group
- Topic: Test Anxiety
- Replies: 62
- Views: 3957
Re: Test Anxiety
I take a few deep breaths. I get less anxious when I know that I studied to my fullest potential, so it puts me in the mindset that I am going to try my BEST. When I start my test and am unable to do the first few questions that makes me more stressed out. So I either take it slow or take the test b...
- Fri Nov 06, 2020 8:30 am
- Forum: Student Social/Study Group
- Topic: Favorite TV shows
- Replies: 277
- Views: 49509
Re: Favorite TV shows
Breaking Bad, Orange is the New Black, How to get Away with Murder, Euphoria! some of my favorites
- Thu Nov 05, 2020 10:25 am
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Why is the 4s state filled before the 3d state?
- Replies: 14
- Views: 938
Re: Why is the 4s state filled before the 3d state?
The energy levels that are lowest are filled up first. Based on experimental data, it was found that the 4S shell has less energy than the 3D shell, so that's why it is filled up first.
- Thu Nov 05, 2020 10:22 am
- Forum: Ionic & Covalent Bonds
- Topic: Homework due date
- Replies: 49
- Views: 2555
Re: Homework due date
Sapling homework is due at 12:59 midnight on Sundays! He also uploaded the new Sapling for week 5 and 6, so it is due next Sunday night. Hope that helps!
- Mon Nov 02, 2020 8:36 am
- Forum: Electronegativity
- Topic: Periodic Table Trend
- Replies: 40
- Views: 2656
Re: Periodic Table Trend
The trends for ionization energy and electronegativity are the same. They increase in electronegativity/ionization energy as you go across a row and up a column. Fluorine is the most electronegative element. This is because for ionization energy, or the energy to remove an electron, the elements wit...
- Mon Nov 02, 2020 8:28 am
- Forum: Student Social/Study Group
- Topic: Forming Virtual Study Group
- Replies: 31
- Views: 1269
Re: Forming Virtual Study Group
I would love to be a part of it! My email is anfishm@gmail.com :)
- Mon Nov 02, 2020 8:25 am
- Forum: Properties of Electrons
- Topic: Sapling #24
- Replies: 7
- Views: 547
Re: Sapling #24
I was confused on this one as well, but I realized that the waves must be continuous. So as Juliana mentioned above, picture the image of the wave side by side, and if its continuous, then you know that the wave is compatible.
- Mon Nov 02, 2020 8:22 am
- Forum: Balancing Chemical Reactions
- Topic: Balancing Equations Coefficient Question
- Replies: 24
- Views: 2791
Re: Balancing Equations Coefficient Question
Yes, you should multiply your coefficients by the same number in order to get whole ratios. That number should be the smallest coefficient possible, or you'll need to simplify. For example, if the coefficient is 1.5, you'd want to multiply by 2. If 3.33, multiply by 3. When you put it in fraction fo...
- Mon Nov 02, 2020 8:18 am
- Forum: Student Social/Study Group
- Topic: Halloween!!!
- Replies: 73
- Views: 4243
Re: Halloween!!!
Happy Halloween!! I went to a very small Halloween "get-together" where I watched scary movies and ate candy :)
- Sun Oct 25, 2020 11:22 pm
- Forum: Properties of Light
- Topic: Webcam for midterm
- Replies: 6
- Views: 495
Re: Webcam for midterm
I'm pretty sure Professor Lavelle sent out an email regarding the webcam and all of its nuances later in Week 2. Additionally, there's an entire page on Chemistry Community answering a ton of those questions. My TA told my session that a cell phone would be okay as well!
- Sun Oct 25, 2020 11:16 pm
- Forum: Student Social/Study Group
- Topic: Textbook sections on the midterm?
- Replies: 3
- Views: 146
Re: Textbook sections on the midterm?
As mentioned above, Lavelle said the MT covers up to 1.D.2 in the textbook and to Week 3 Wednesday lecture. Quantum numbers, s, p, d-orbitals, etc., are not on MT 1.
- Sun Oct 25, 2020 11:05 pm
- Forum: SI Units, Unit Conversions
- Topic: Do I need to do very single textbook question on the syllabus?
- Replies: 34
- Views: 1718
Re: Do I need to do very single textbook question on the syllabus?
Like everybody has mentioned above, it's your call. They aren't collected, but they help you prepare for exams and the coming up midterm. If you look at the syllabus, there are multiple practice problems Professor Lavelle recommended. Whatever feels best for you!
- Sun Oct 25, 2020 11:02 pm
- Forum: Properties of Electrons
- Topic: rydberg equation
- Replies: 8
- Views: 392
Re: rydberg equation
In the Rydberg equation, n1 represents the lower energy level and the n2 value represents the higher energy level. n2 has to be greater than n1 (positive results)
- Sun Oct 18, 2020 12:57 pm
- Forum: Student Social/Study Group
- Topic: How are you studying?
- Replies: 204
- Views: 24717
Re: How are you studying?
Studying is subjective and depends on how you work best personally. For me, I watch the lectures while taking notes to highlight key points. I also do the Sapling along with homework problems if I need additional help understanding a concept. Reading the textbook as well!! Use a planner or calendar ...
- Sun Oct 18, 2020 9:49 am
- Forum: Student Social/Study Group
- Topic: Discussion 2A GroupMe
- Replies: 2
- Views: 137
Re: Discussion 2A GroupMe
Thank you!!!!
- Sun Oct 18, 2020 9:47 am
- Forum: Administrative Questions and Class Announcements
- Topic: UCLA Store Updates on Ebook/Sapling access card
- Replies: 16
- Views: 739
Re: UCLA Store Updates on Ebook/Sapling access card
I ordered my Sapling textbook with the shipping option about a week before school started, and I received it in the middle of the second week of school. I kept checking the UCLA bookstore site for when the status of the book switched from "processing" to "shipping". They also sen...
- Sun Oct 18, 2020 9:43 am
- Forum: General Science Questions
- Topic: Writing Formulas
- Replies: 10
- Views: 439
Re: Writing Formulas
Equations should generally be given to us, but for our future in chemistry, it is best to start becoming familiar as well as memorizing them.