Search found 105 matches
- Sat Mar 13, 2021 5:46 pm
- Forum: Student Social/Study Group
- Topic: How do you deal with burnout?
- Replies: 144
- Views: 26471
Re: How do you deal with burnout?
I highly recommend taking breaks or taking walks in the middle of study or work sessions. Like don't spend the breaks on your phone but do something that lets your brain take a break essentially.
- Sat Mar 13, 2021 5:46 pm
- Forum: Student Social/Study Group
- Topic: How do you deal with burnout?
- Replies: 144
- Views: 26471
Re: How do you deal with burnout?
I highly recommend taking breaks or taking walks in the middle of study or work sessions. Like don't spend the breaks on your phone but do something that lets your brain take a break essentially.
- Fri Mar 12, 2021 12:05 am
- Forum: Student Social/Study Group
- Topic: How are y'all doing?
- Replies: 46
- Views: 3493
Re: How are y'all doing?
I feel like I lost all motivation this quarter, but I'm taking less classes next quarter so I hope everything goes well.
- Fri Mar 12, 2021 12:03 am
- Forum: Student Social/Study Group
- Topic: chem community points
- Replies: 23
- Views: 1426
Re: chem community points
50 points but don't forget that extra posts from previous weeks don't count I think
- Wed Mar 10, 2021 9:44 pm
- Forum: Student Social/Study Group
- Topic: Planning on dorming in the Fall?
- Replies: 61
- Views: 4842
Re: Planning on dorming in the Fall?
I plan on dorming in the Fall if I'm able to be vaccinated by then. Remote learning or not, I'm going stir crazy from being home 24/7
- Wed Mar 10, 2021 9:43 pm
- Forum: Student Social/Study Group
- Topic: It is possible to study for the final in one day?
- Replies: 44
- Views: 5096
Re: It is possible to study for the final in one day?
Studying for the final in one day is definitely not it. You gotta split it so your don't overload yourself in one study session. I did that for the last midterm and learned my lesson :(
- Fri Mar 05, 2021 5:24 pm
- Forum: Student Social/Study Group
- Topic: Fave movie/show
- Replies: 67
- Views: 6505
Re: Fave movie/show
My favorite movie of all time is Interstellar.
- Fri Mar 05, 2021 4:54 pm
- Forum: Student Social/Study Group
- Topic: What organizations are you guys in?
- Replies: 53
- Views: 4358
Re: What organizations are you guys in?
I've gotten involved in Vietnamese Community Health (VCH), and I plan to get involved in more orgs and clubs once we get back on campus.
- Fri Mar 05, 2021 12:32 am
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: What was your favorite chem topic?
- Replies: 137
- Views: 15185
Re: What was your favorite chem topic?
I found quantum to be really great because it was all plug and chug lol
- Tue Mar 02, 2021 10:14 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: What does (gr) mean?
- Replies: 4
- Views: 1707
What does (gr) mean?
I saw (gr) in question 6M.3 for (d) and was wondering what that means. Also, does this have any significance in cell diagrams and galvanic cells in general?
- Tue Mar 02, 2021 10:10 pm
- Forum: Student Social/Study Group
- Topic: Spring Break
- Replies: 53
- Views: 4582
Re: Spring Break
I'm going to just binge shows and play video games. Forgetting about school and relaxing is so nice in breaks like this.
- Fri Feb 26, 2021 7:21 pm
- Forum: Balancing Redox Reactions
- Topic: Sapling #18 for Wk 7 and 8
- Replies: 3
- Views: 252
Sapling #18 for Wk 7 and 8
Hello, can someone help with #18? I am not sure how to get started with this problem. Thanks in advance!
- Fri Feb 26, 2021 2:56 am
- Forum: Student Social/Study Group
- Topic: Anxiety
- Replies: 109
- Views: 11425
Re: Anxiety
This probably isn't the best advice but I literally just study to the point I am no longer nervous. I kinda just do as many practice problems as I can and it just makes more confident in doing chemistry problems in regards to future exams.
- Wed Feb 24, 2021 10:04 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Chem 14 B Final
- Replies: 34
- Views: 1957
Re: Chem 14 B Final
I'm assuming it's going to be just like last quarter for Lavelle's 14A class where the final was cumulative and the amount of questions for each section was based off of the amount of time we spent on each unit.
- Wed Feb 24, 2021 8:10 pm
- Forum: Student Social/Study Group
- Topic: Balance / Self Care Tips
- Replies: 62
- Views: 4692
Re: Balance / Self Care Tips
Keeping a to-do list for the day really keeps you on top of everything. Ever since I starting making a to-do list for my daily tasks, it's been much easier managing time for each task for the day.
- Wed Feb 24, 2021 9:21 am
- Forum: Balancing Redox Reactions
- Topic: Sapling #3 for Wk 7 and 8
- Replies: 3
- Views: 279
Sapling #3 for Wk 7 and 8
Hello, can somebody help me with this question? Thanks in advance!
- Fri Feb 19, 2021 9:13 pm
- Forum: Student Social/Study Group
- Topic: Post Midterm 2 De-stressing
- Replies: 92
- Views: 10329
Re: Post Midterm 2 De-stressing
I'm probably just going to watch some shows and play video games. Perfect way to destress in my opinion.
- Fri Feb 19, 2021 9:12 pm
- Forum: Student Social/Study Group
- Topic: Classes for next quarter?
- Replies: 165
- Views: 24689
Re: Classes for next quarter?
I'll be taking Chem 14C, LS 7B and Psych 10
- Fri Feb 19, 2021 7:38 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Gas Constant R
- Replies: 43
- Views: 4561
Re: Gas Constant R
It really just depends what you want your answer to end in. 8.314 is typically used when you want your answer to end in joules.
- Thu Feb 18, 2021 8:06 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Adiabatic
- Replies: 26
- Views: 1310
Re: Adiabatic
I found this Chemistry Community post from Lavelle in which he posted a list of thermodynamic definitions. https://lavelle.chem.ucla.edu/forum/viewtopic.php?f=128&t=9661 Adiabatic (also called adiabatically isolated system) An adiabatically isolated system has only adiabatic boundary sectors. En...
- Wed Feb 17, 2021 9:12 pm
- Forum: Administrative Questions and Class Announcements
- Topic: MIDTERM 2
- Replies: 9
- Views: 664
Re: MIDTERM 2
It's the lectures from weeks 4-6
- Fri Feb 12, 2021 10:50 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: q equation
- Replies: 21
- Views: 3800
Re: q equation
Both solve for q and m or n in the equation represents specific heat capacity or molar heat capacity.
- Fri Feb 12, 2021 9:12 pm
- Forum: Student Social/Study Group
- Topic: Thoughts on Upcoming Midterm 2
- Replies: 41
- Views: 2191
Re: Thoughts on Upcoming Midterm 2
I've been feeling nervous myself. I feel like the thermodynamics section ramped up so much in comparison to previous units. We still have a week left till the midterm though so I hope everyone is confident by then.
- Fri Feb 12, 2021 5:07 pm
- Forum: Administrative Questions and Class Announcements
- Topic: UA Sessions: Midterm 2 Review
- Replies: 13
- Views: 867
Re: UA Sessions: Midterm 2 Review
I remember some UA sessions where they did midterm review for the first hour and new material for the second half.
- Fri Feb 12, 2021 6:34 am
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Residual entropy
- Replies: 4
- Views: 636
Re: Residual entropy
I believe it'd be N2O since it can have multiple orientations and also has resonance. Also, I found this other post on Chemistry Community to be very helpful in relation to your question. https://lavelle.chem.ucla.edu/forum/viewtopic.php?t=10290 To calculate the residual entropy, you need to know ho...
- Wed Feb 10, 2021 4:03 am
- Forum: Student Social/Study Group
- Topic: Points needed to pass?
- Replies: 76
- Views: 12707
Re: Points needed to pass?
From what I've heard for this class, getting more than 200 points lets you pass the class. Basically, a 50% in this class is a passing grade.
- Sun Feb 07, 2021 1:05 am
- Forum: Student Social/Study Group
- Topic: Favorite TV shows
- Replies: 277
- Views: 62777
Re: Favorite TV shows
I've been watching Neon Genesis Evangelion. It's such a classic show.
- Sun Feb 07, 2021 12:46 am
- Forum: Calculating Work of Expansion
- Topic: Sapling #14 for Wk 3 and 4
- Replies: 12
- Views: 678
Sapling #14 for Wk 3 and 4
Hello, can someone help me with this problem for Sapling? Thanks in advance!
- Sat Feb 06, 2021 7:21 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Chemistry Community Posts
- Replies: 17
- Views: 711
Re: Chemistry Community Posts
It depends on your TA but I heard from others that you can still get chem community points back if you make up for the posts that you missed for a certain week.
- Fri Feb 05, 2021 1:07 am
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Work
- Replies: 39
- Views: 1967
Re: Work
Hello, similar to what everyone said, when there is a negative value for work that means the work is done by the system whereas when the value for w is positive work is being done on the system by the surroundings. I found this video by the Organic Chemistry Tutor to be very helpful! https://www.you...
- Thu Feb 04, 2021 11:42 pm
- Forum: General Science Questions
- Topic: Tips
- Replies: 53
- Views: 2919
Re: Tips
I know that this is a slightly different question, but I would also really appreciate any tips that you guys have for studying for the midterms or studying for this class in general. Similar to what others have said, I've found attending UA sessions, textbook and Sapling to work really well. Also, ...
- Sat Jan 30, 2021 5:33 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: is HClO3 weak or strong? [ENDORSED]
- Replies: 49
- Views: 5227
Re: is HClO3 weak or strong? [ENDORSED]
Yes it is a strong acid
- Sat Jan 30, 2021 5:33 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Chem 14C Spring Quarter
- Replies: 11
- Views: 784
Re: Chem 14C Spring Quarter
It's seems like the only professor for 14C is Castillo
- Thu Jan 28, 2021 12:52 am
- Forum: Polyprotic Acids & Bases
- Topic: 6E.1 for Textbook
- Replies: 2
- Views: 257
Re: 6E.1 for Textbook
AdilaAhmed3I wrote:They simply factored out that negative. Your set up is correct and will get the same answer
Oh I see, how did I not see that loll
- Thu Jan 28, 2021 12:03 am
- Forum: Polyprotic Acids & Bases
- Topic: 6E.1 for Textbook
- Replies: 2
- Views: 257
6E.1 for Textbook
Hello, this is a really minor problem but for 6E.1 in the textbook, the answer in the solutions manual puts in the c value for the quadratic equation as positive. Are you supposed to do that or am I doing something wrong? I put a screenshot of my work and the answer in the solution manual for compar...
- Wed Jan 27, 2021 11:16 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Lecture Content for MT1
- Replies: 4
- Views: 243
Re: Lecture Content for MT1
I believe it's up to last Friday's lecture, so that would be Lecture #8 (Fri, 01/22/2021)
- Sat Jan 23, 2021 10:10 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: pKa and Ka
- Replies: 27
- Views: 1206
Re: pKa and Ka
The smaller the pka and higher the Ka the stronger the acid and vice versa the higher the pka and smaller the Ka the weaker the acid.
- Sat Jan 23, 2021 10:09 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Solids in Ice Tables
- Replies: 11
- Views: 1094
Re: Solids in Ice Tables
Anything solid or liquid is never included in an ice table.
- Fri Jan 22, 2021 1:05 am
- Forum: Student Social/Study Group
- Topic: Calculators
- Replies: 52
- Views: 4660
Re: Calculators
I was able to use a graphing calculator last quarter for Lavelle's Chem 14A class so it should be okay.
- Thu Jan 21, 2021 9:26 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Studying for Midterm #1
- Replies: 63
- Views: 3810
Re: Studying for Midterm #1
Textbook problems and UA sessions are your go to for studying in this class. Exposing yourself to different problems just helps you in the long run with exams.
- Thu Jan 21, 2021 12:18 am
- Forum: Phase Changes & Related Calculations
- Topic: Vapor vs gas
- Replies: 121
- Views: 18373
Re: Vapor vs gas
They're essentially the same thing
- Sat Jan 16, 2021 8:48 pm
- Forum: Ideal Gases
- Topic: Units of Temperature
- Replies: 82
- Views: 4987
Re: Units of Temperature
For chemistry problems, I'm pretty sure you'd always use kelvin.
- Fri Jan 15, 2021 9:53 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Exam Format
- Replies: 15
- Views: 1343
Re: Exam Format
So we have just the 50 minute lecture time for the exam? And about how long did you have for each question? Like were there a lot of shorter questions or was it just a few questions that took a while? For me, I ended the midterms with a lot of time since a decent amount of questions were conceptual...
- Thu Jan 14, 2021 11:40 pm
- Forum: Administrative Questions and Class Announcements
- Topic: More Audio Visual Focus Topics
- Replies: 8
- Views: 453
Re: More Audio Visual Focus Topics
For last quarter, he only had it for the fundamentals and quantum. I'm assuming it'll be the same and there will be no addition of the audio visual focus topics.
- Wed Jan 13, 2021 10:02 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: pH and pKa
- Replies: 6
- Views: 230
pH and pKa
I know that they're both different, but how can I differentiate between the two in terms of application and concepts?
- Wed Jan 13, 2021 5:59 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Left vs. Right
- Replies: 29
- Views: 1295
Re: Left vs. Right
They're the same and the terms are used when you look at the K value to determine whether reactants or products are favored in a reaction.
- Fri Jan 08, 2021 9:24 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Sapling Wk 1 Q2
- Replies: 3
- Views: 435
Sapling Wk 1 Q2
Hello, I've been having trouble trying to work this problem. I don't know if I'm doing it right but I multiplied the given equilibrium moles of O2 by 2 to get 0.240 mol for SO2. I then added the equilibrium moles of SO2 and O2 to get 0.360, which I then subtracted from the 0.820 initial moles of SO3...
- Fri Jan 08, 2021 7:28 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Q and K
- Replies: 46
- Views: 2213
Re: Q and K
You can calculate Q to figure out where the reaction will proceed if given the equilibrium constant, K. Similar to what Silvi said, when Q<K the reaction will proceed to the right and vice versa when Q>K the reaction will proceed to the left.
- Fri Jan 08, 2021 5:20 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Audio-Visual Topics
- Replies: 13
- Views: 739
Re: Audio-Visual Topics
I think it's just for equilibrium, since for 14A the audio-visual topics were only for the fundamentals review and early quantum.
- Thu Jan 07, 2021 9:05 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Sapling Assignments
- Replies: 30
- Views: 2386
Re: Sapling Assignments
They're optional but I found them to be helpful for Chem 14A last quarter in terms of review and getting used to Sapling.
- Wed Jan 06, 2021 12:57 pm
- Forum: Student Social/Study Group
- Topic: Advice for someone who didn't take 14A with professor Lavelle
- Replies: 61
- Views: 4075
Re: Advice for someone who didn't take 14A with professor Lavelle
Like everyone else has replied to on this post, I highly recommend the UA workshops because they expose you do different types of problems that are very similar to questions on midterms and final exams.
- Thu Dec 10, 2020 1:39 pm
- Forum: Bronsted Acids & Bases
- Topic: How do we know if its an acid or base?
- Replies: 3
- Views: 291
Re: How do we know if its an acid or base?
Going off of what Samantha said, it really depends on the context of the problem whether the compound is being used as an acid or base. Molecules that can act as both as an acid or base is considered amphiprotic. For example, HCO3- can become CO3^2- or H2CO3. Edit: Sorry I didn't mean to say amphote...
- Wed Dec 09, 2020 9:43 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: lone pairs and 180 degrees
- Replies: 4
- Views: 644
Re: lone pairs and 180 degrees
While I can't really explain why linear molecules can have lone pairs, I know for a fact that linear molecules can have three or four lone pairs. I put an attachment for the VSEPR geometries and in the bottom right there are two linear VSEPR geometries with three or four lone pairs. I think it's bec...
- Wed Dec 09, 2020 9:38 pm
- Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
- Topic: Bonding sites
- Replies: 2
- Views: 360
Re: Bonding sites
For hydrogen bonding, we know that a hydrogen bond can only occur between an H atom and a F, O, or N atom. When looking at thymine, we need to look at the amount of hydrogen atoms and the amount of lone pairs in any atom that is F, O, or N. In the thymine molecule, there's two hydrogen atoms, so tha...
- Wed Dec 09, 2020 9:16 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Do we need to memorize all 15 shapes
- Replies: 5
- Views: 423
Re: Do we need to memorize all 15 shapes
I think you should memorize all of them but I remember one of the UAs saying that there are some shapes such as T-shape being pretty rare to occur in problems. The ones I put an emphasis on were bent, linear, tetrahedral, trigonal planar, and trigonal pyramidal but yeah I'd still try and memorize al...
- Wed Dec 09, 2020 5:01 pm
- Forum: Naming
- Topic: Aqua vs Hydrate
- Replies: 14
- Views: 1167
Re: Aqua vs Hydrate
Yes I think I saw in another chemistry community post that when H2O is within the coordination compound, it's name is aqua. For example, in the coordination compound [CrCl3(NH3)2(OH2)]+ , H2O would be referred to as aqua. When outside of the bracket, H2O is referred to as hydrate. Honestly, I'm not ...
- Mon Dec 07, 2020 10:48 pm
- Forum: Identifying Acidic & Basic Salts
- Topic: Sapling Wk 10 Q7
- Replies: 2
- Views: 196
Sapling Wk 10 Q7
Hello, I'm having trouble classifying whether a salt is acidic, basic, or neutral. Can someone explain to me how to determine what these salts are? Thanks in advance!
- Fri Dec 04, 2020 10:36 pm
- Forum: Ionic & Covalent Bonds
- Topic: Polar and Nonpolar
- Replies: 37
- Views: 2173
Re: Polar and Nonpolar
Don't forget that a molecule can have polar bonds but can still be a nonpolar molecule due to its shape.
- Fri Dec 04, 2020 5:08 pm
- Forum: Student Social/Study Group
- Topic: How are you?
- Replies: 154
- Views: 21608
Re: How are you?
Super anxious but studying and doing more practice problems makes me feel more ready for the upcoming final :)
- Fri Dec 04, 2020 12:10 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: List of Ligands
- Replies: 5
- Views: 216
Re: List of Ligands
There's a list of ligands on Dr. Lavelle's Chem 14A site titled "Naming Coordination Compounds." I'm just going to assume he wants us to memorize those since they're on his site.
- Thu Dec 03, 2020 7:01 pm
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: Weak/strong acids/bases
- Replies: 2
- Views: 153
Re: Weak/strong acids/bases
Adding onto what the post above said, an example of this could be the strong acid HCl and the weak acid HF. We can tell that HCl is a strong acid because it's bond between H and Cl is weak. Since the Cl atom has a larger atomic radius this creates a longer bond length resulting in a weak bond. The w...
Re: Ligands
There is a pdf on Lavelle's Chem 14A website titled "Naming Coordination Compounds." I was told that these are the main ones that Lavelle wants us to memorize.
- Tue Dec 01, 2020 4:20 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 4095573
Re: Post All Chemistry Jokes Here
A photon checks into a hotel and the bellboy asks, "Can I take your bags?" The photon answers, "No thanks, I'm travelling light."
- Wed Nov 25, 2020 9:39 pm
- Forum: Hybridization
- Topic: Clarification on 11/23 Monday's Lecture
- Replies: 5
- Views: 283
Re: Clarification on 11/23 Monday's Lecture
I think it is too because I can't see any way you'd get sp3 for the hybridization of ethylene, only sp2.
- Wed Nov 25, 2020 9:36 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Sapling Question #12
- Replies: 2
- Views: 128
Re: Sapling Question #12
That's really odd, I have the same exact lewis structure as you and it says that it's correct. Did you get sp^3 for the hybridization of the carbon and oxygen atoms and say that it was polar?
- Tue Nov 24, 2020 9:50 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: VSEPR Simulation
- Replies: 2
- Views: 351
VSEPR Simulation
Hello, I just wanted to link this here since I found this simulation to be very helpful for me when visualizing VSEPR shapes. Just wanted to link this out there to anyone else having trouble visualizing VSEPR shapes.
https://phet.colorado.edu/sims/html/mol ... es_en.html
https://phet.colorado.edu/sims/html/mol ... es_en.html
- Mon Nov 23, 2020 5:33 pm
- Forum: DeBroglie Equation
- Topic: De broglie equation versus E=hv
- Replies: 10
- Views: 880
Re: De broglie equation versus E=hv
I believe the De broglie equation is used when determining whether the object being evaluated has wavelike properties or not. For example, if you're given the energy of an object that is not light, you can use the E=hv equation to find the velocity and use that velocity to plug into the De broglie e...
- Mon Nov 23, 2020 5:20 pm
- Forum: Administrative Questions and Class Announcements
- Topic: UA Sessions for Thanksgiving
- Replies: 1
- Views: 106
UA Sessions for Thanksgiving
I was just wondering, will there still be UA sessions for this week?
- Sat Nov 21, 2020 4:46 pm
- Forum: Student Social/Study Group
- Topic: Study Tips for Final Exam
- Replies: 57
- Views: 3822
Re: Study Tips for Final Exam
The textbooks questions and readings have helped me a lot in understanding how to do calculation based problems along with conceptual based problems. Also, the workshops that happen every week are so helpful, they expose you to different types of questions and have help me a lot on the midterms.
- Sat Nov 21, 2020 4:43 pm
- Forum: Ionic & Covalent Bonds
- Topic: Covalent Character
- Replies: 14
- Views: 2535
Re: Covalent Character
I remember there was like a scale to determine covalent or ionic character where if the electronegativity difference is greater than 1.5 its more ionic and if less an 1.5 its more covalent.
- Mon Nov 16, 2020 6:36 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Counting Valence Electrons D Orbital Vs S and P Orbitals
- Replies: 3
- Views: 825
Re: Counting Valence Electrons D Orbital Vs S and P Orbitals
When we look at the periodic table, we know that 5s and 5p subshells are of a higher energy level than 4d. The electron configuration for Sb is [Kr]4d^10 5s^2 5p^3. We know that valence electrons are the outermost electrons of an atom, so when we look at this electron configuration, the 5 electrons ...
- Mon Nov 16, 2020 6:01 pm
- Forum: Bond Lengths & Energies
- Topic: Boiling Point of Molecules
- Replies: 2
- Views: 173
Boiling Point of Molecules
Hello, I was going over the worksheet from Riya Shah's workshop today and one of the questions asks to put Br2, Cl2, and I2 from lowest to highest BP. Since these molecules only have LDFs, the molecule with more electrons and larger molar mass form stronger LDFs in which the answer was Cl2<Br2<I2. H...
- Mon Nov 16, 2020 1:31 am
- Forum: Resonance Structures
- Topic: Textbook 2C.17
- Replies: 2
- Views: 209
Textbook 2C.17
Hello, I was wondering how do you figure out which resonance structure makes the most dominant contribution to a resonance hybrid? Thanks in advance!
- Fri Nov 13, 2020 7:58 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Midtern #2
- Replies: 6
- Views: 232
Re: Midtern #2
We use the same sheets we used on the last midterm which was the equations and constants sheet along with a periodic table.
- Thu Nov 12, 2020 8:32 pm
- Forum: Dipole Moments
- Topic: induced dipole vs dipole
- Replies: 11
- Views: 971
Re: induced dipole vs dipole
I believe induced dipole-induced dipole bonds occurs among all atoms and molecules. This occurs when the molecule temporarily distorts another neighboring molecule causing a temporary attraction causing the induced dipole-induced dipole bond. Dipole-dipole interactions can only occur between two pol...
- Wed Nov 11, 2020 7:50 pm
- Forum: Dipole Moments
- Topic: Dipole dipole vs LDF
- Replies: 10
- Views: 3541
Re: Dipole dipole vs LDF
Dipole dipole and LDFs are both intermolecular forces. LDFs occur between every atom and molecule in intermolecular forces, while dipole dipole only occurs between polar molecules that are dipole.
- Tue Nov 10, 2020 5:53 pm
- Forum: Student Social/Study Group
- Topic: Test Anxiety
- Replies: 62
- Views: 4724
Re: Test Anxiety
I find taking deep breathes really helps. Also, whenever I find myself taking too much time on a problem I just move on the next problem and go back to it later. What helped me the most is just doing practice problems, so when it came to the test I knew what to do immediately.
- Mon Nov 09, 2020 4:56 pm
- Forum: Student Social/Study Group
- Topic: Mid-quarter Check in
- Replies: 67
- Views: 5366
Re: Mid-quarter Check in
The quarter system has been going pretty fast but I've been managing my time pretty well and am able to keep up. I'm beginning to feel burnt out with all these midterms and work going around but we're already halfway there.
- Thu Nov 05, 2020 7:45 pm
- Forum: Lewis Structures
- Topic: Sapling Lewis Strucutres
- Replies: 5
- Views: 229
Re: Sapling Lewis Strucutres
I remember Lavelle saying that in nature wants to be stable. By looking at the overall formal charge of a molecule, the Lewis structure that would contribute the most I assume would be the most stable molecule.
- Wed Nov 04, 2020 11:39 pm
- Forum: Lewis Structures
- Topic: Sapling Week 5-6 Q4
- Replies: 1
- Views: 94
Sapling Week 5-6 Q4
Hello, can someone help me with this? I know that double bonds are shorter in pm than single bonds, but I'm fully understanding the problem as I keep getting it wrong. Thanks in advance!
- Wed Nov 04, 2020 11:22 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Representing Electron Configurations for P-orbitals
- Replies: 6
- Views: 268
Re: Representing Electron Configurations for P-orbitals
I believe the p^n format is less descriptive than the px, py, pz format. The latter format is more specific and helps display Hund's rule in which each orbital in the 2p subshell is occupied with one electron before any orbital has two electrons.
- Tue Nov 03, 2020 7:05 pm
- Forum: Trends in The Periodic Table
- Topic: Why is the ionization energy of O lower than N?
- Replies: 13
- Views: 1863
Why is the ionization energy of O lower than N?
I remember hearing that ionization energy increases across a period. Why does oxygen have a lower ionization energy than nitrogen?
- Tue Nov 03, 2020 6:46 pm
- Forum: Electronegativity
- Topic: Periodic Table Trend
- Replies: 40
- Views: 2845
Re: Periodic Table Trend
They both increase across a period and decrease down a group.
- Fri Oct 30, 2020 7:14 pm
- Forum: DeBroglie Equation
- Topic: Sapling Homework #14
- Replies: 2
- Views: 277
Re: Sapling Homework #14
For the second part of this problem, you want to use the de Broglie equation and rearrange it to find the velocity of the electron. So after rearranging the equation it should be v = h/m λ. Convert the wavelength to meters, and plug in the values and you should get 290.96 m.s^-1 for velocity. I woul...
- Thu Oct 29, 2020 3:49 am
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Atomic Spectra Post Module Question
- Replies: 2
- Views: 222
Re: Atomic Spectra Post Module Question
With the wavelength, you can look at the electromagnetic spectrum and compare your wavelength to the wavelengths that are on the spectrum. Here is an attachment, you can see that the visible light portion is around 380 nm to ~700 nm. I just memorized the general parts of the electromagnetic spectrum...
- Wed Oct 28, 2020 6:22 pm
- Forum: DeBroglie Equation
- Topic: sapling hw problem
- Replies: 5
- Views: 537
Re: sapling hw problem
For the second part of this problem, you want to use the de Broglie equation and rearrange it to find the velocity of the electron. So after rearranging the equation it should be v = h/m λ. Convert the wavelength to meters, and plug in the values and you should get 382.84 m.s^-1. I would then use th...
- Tue Oct 27, 2020 11:34 pm
- Forum: Photoelectric Effect
- Topic: Work function or incoming light
- Replies: 6
- Views: 241
Re: Work function or incoming light
When the problem asks to find the energy to remove an electron, that would be considered the work function or threshold energy. If a problem asks for the energy that causes the photoejection of an electron, that would be the incoming light or incident light.
- Mon Oct 26, 2020 6:37 pm
- Forum: Student Social/Study Group
- Topic: Midterm
- Replies: 5
- Views: 315
Re: Midterm
I think when Dr. Lavelle said up to 1D.2, he just meant the section to read up to for the 1D section. I don't think there are any problems you need to do because on the outline, he did not assign the problem 1D.2. I think he is just going to test us on concepts.
- Fri Oct 23, 2020 4:56 pm
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: Heisenberg Indeterminacy Q from Workshop
- Replies: 1
- Views: 178
Heisenberg Indeterminacy Q from Workshop
Hello, I was wondering if someone could help me with this. I was late to Kate Santoso's workshop last night. Thanks in advance! Q1A. The uncertainty in the momentum of a football thrown by Tom Brady during the superbowl traveling at 40 m/s is 1 x 10-6 of its momentum. What is its uncertainty in posi...
- Fri Oct 23, 2020 2:31 am
- Forum: DeBroglie Equation
- Topic: Sapling Hw 2 #19
- Replies: 10
- Views: 579
Re: Sapling Hw 2 #19
I would just make sure to check for unit conversions. Don't forget that the joule unit in Planck's constant for the De Broglie equation is 1 kg.m^2.s^-2 Does this mean that you do not input the value as 6.626*10^-34 J.s into the equation? My bad, I didn't mean to put the 1 before the kg.m^2.s^-2. Y...
- Fri Oct 23, 2020 12:13 am
- Forum: General Science Questions
- Topic: When to use sig figs
- Replies: 19
- Views: 971
Re: When to use sig figs
I believe that in the middle of calculations, you wouldn't round down values to sig figs. However, when calculating your final answer, you would then use sig figs because if you used sig figs in the middle of the problem and then used those values to calculate the solution, the answer would be less ...
- Thu Oct 22, 2020 11:44 pm
- Forum: DeBroglie Equation
- Topic: Sapling Hw 2 #19
- Replies: 10
- Views: 579
Re: Sapling Hw 2 #19
I would just make sure to check for unit conversions. Don't forget that the joule unit in Planck's constant for the De Broglie equation is 1 kg.m^2.s^-2
- Thu Oct 22, 2020 7:59 pm
- Forum: Student Social/Study Group
- Topic: Midterm study
- Replies: 5
- Views: 259
Re: Midterm study
I suggest just redoing practice problems from the textbook and post-assessment modules. Also, the workshops are also really helpful if you want extra practice.
- Mon Oct 19, 2020 7:29 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Saping HW Q.8
- Replies: 8
- Views: 456
Saping HW Q.8
I'm having trouble figuring out to get started with this problem. Thanks in advance! "A blue line is observed at 486.1 nm in the spectrum of atomic hydrogen. Determine the values of n for the beginning and ending energy levels of the electron during the emission of energy that leads to this spe...
- Sat Oct 17, 2020 5:57 pm
- Forum: Student Social/Study Group
- Topic: How are you studying?
- Replies: 204
- Views: 30818
Re: How are you studying?
I've just been taking notes from the lectures, and doing the textbook problems assigned for each unit. Something that really helps is attending the workshops, the UAs explain everything so well and the worksheets help out so much.
- Fri Oct 16, 2020 8:20 pm
- Forum: Einstein Equation
- Topic: E=hv
- Replies: 8
- Views: 693
Re: E=hv
Dr. Lavelle changed the negative sign in -4.09x10^-19 J to positive sign because I think he specifically stated that energy cannot be negative. The negative sign represented that the electrons energy decrease and was released as electromagnetic radiation. If you plug the -4.09x10^-19 and divide it b...
- Fri Oct 16, 2020 6:53 am
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Q.42 for Atomic Spectra Post Module
- Replies: 4
- Views: 202
Q.42 for Atomic Spectra Post Module
An excited hydrogen atom emits light with a frequency of 1.14 x 1014 Hz to reach the energy level n = 4. In what principle quantum level did the electron begin? Does anyone know how to do this with the E = -hR/n^2 equation or does it have to be the Rydberg equation? I just remember Dr. Lavelle sayin...
- Thu Oct 15, 2020 4:40 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Week 2&3 Sapling Homework
- Replies: 1
- Views: 90
Re: Week 2&3 Sapling Homework
Yes, it's due midnight Sunday Week 3 (Oct. 25) since we will still be learning Quantum next week
- Tue Oct 13, 2020 6:08 pm
- Forum: Photoelectric Effect
- Topic: Photoelectric Effect Post-Module #28
- Replies: 4
- Views: 172
Re: Photoelectric Effect Post-Module #28
For Part A you use KE = 1/2 mv^2. The mass of an electron is approx 9.109*10^-31 kg. Therefore, by plugging in what's given into the formula, you should have (1/2)*(9.109*10^-31)(6.61*10^5)^2 which should result in the answer.
- Sat Oct 10, 2020 12:14 am
- Forum: Molarity, Solutions, Dilutions
- Topic: Question G.25 in Fundamentals
- Replies: 2
- Views: 145
Question G.25 in Fundamentals
Hello, can someone explain this problem to me? I am having trouble understanding the problem. I thought that mols of solute don't change in a dilution. G.25 Practitioners of the branch of alternative medicine known as homeopathy claim that very dilute solutions of substances can have an effect. Is t...