Search found 98 matches
- Sat Mar 13, 2021 10:44 pm
- Forum: Ideal Gases
- Topic: Standard temperature
- Replies: 10
- Views: 679
Re: Standard temperature
It would be either 25 C or 298 K.
- Sat Mar 13, 2021 10:43 pm
- Forum: Student Social/Study Group
- Topic: Note Taking
- Replies: 145
- Views: 15058
Re: Note Taking
I usually take notes of the lectures first and then take notes from the textbook. I feel like reading the information just cements the ideas and topics we learned in the lecture. From there, I write on note cards any information that I might need to remember and make an outline with answers and solu...
- Sat Mar 13, 2021 10:41 pm
- Forum: Student Social/Study Group
- Topic: How to Reduce Nervousness before getting results
- Replies: 63
- Views: 4718
Re: How to Reduce Nervousness before getting results
I usually try to forget that I took an exam and remind myself that it's done and I can't change anything. With this, I begin to relax and try to move on from it by doing self-care and relaxing. Take care of yourself first before anything else.
- Sat Mar 13, 2021 10:21 pm
- Forum: Student Social/Study Group
- Topic: Plans for Summer/school year
- Replies: 34
- Views: 1465
Plans for Summer/school year
Hello everyone! I was just wondering if anyone had any plans for the summer/next school year. Any clubs, programs, or special classes that you're interested in? Any events (i.e. movies, tv shows, online events) that you're interested in. Being in quarantine has really made me miss being social and a...
- Sat Mar 13, 2021 10:15 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Temperature of Standard Conditions
- Replies: 5
- Views: 460
Re: Temperature of Standard Conditions
I agree! Usually, standard conditions will either be 25 C or 298 K. However, I believe it will be explicitly mentioned in exams what the temperature will be so there's less confusion about it.
- Sat Mar 13, 2021 10:13 pm
- Forum: Student Social/Study Group
- Topic: Low Grades & Graduate School
- Replies: 22
- Views: 1582
Re: Low Grades & Graduate School
I don't think you can retake a class if you get a C; however, we must also remember that we are in a pandemic and it will affect us all differently. I believe that schools or programs will understand your grades if they are not what you want. Just remember to take care of yourself first!
- Sat Mar 13, 2021 10:09 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: sign for Eo when reversing rxn
- Replies: 11
- Views: 723
Re: sign for Eo when reversing rxn
Kushaal Madadi 2F wrote:Yes. However, when multiplying the reaction by a factor, Eo remains the same (unlike Gibbs Free Energies and Enthalpies of Formation).
If I may, why would Eo remain the same when being multiplied? Thanks in advance!
- Sat Mar 13, 2021 10:06 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Final Bonus Q's
- Replies: 7
- Views: 409
Re: Final Bonus Q's
I agree! It would most likely be 4 points, but we can hope that it might be more!
- Sat Mar 13, 2021 10:04 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Concentration Equations
- Replies: 2
- Views: 187
Re: Concentration Equations
Yes, I agree! The Nernst equation can be used for galvanic/voltaic cells since they are also concentration cells.
- Sat Mar 13, 2021 10:01 pm
- Forum: Student Social/Study Group
- Topic: Left/Right Electrode
- Replies: 9
- Views: 609
Re: Left/Right Electrode
If the question says that it is a galvanic cell, then it means that Ecell must be positive. Usually, as everyone else said, the cathode will be reduced and therefore on the right while the anode will be oxidized and on the left. Sometimes though, they might only give the standard potentials, so this...
- Sat Mar 13, 2021 9:54 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Free Energy of Activation
- Replies: 4
- Views: 333
Re: Free Energy of Activation
I think so too. It might be the energy difference between the transition state and the reactants, but I am also not completely sure.
- Sat Mar 13, 2021 9:49 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Gibbs Free Energy and Maximum Nonexpansion Work
- Replies: 5
- Views: 350
Re: Gibbs Free Energy and Maximum Nonexpansion Work
From what I've read from the textbook, I believe it explains that electrical work is a type of non-expansion because it moves electrons without changing the volume. I also believe they are closely related, but correct me if I'm wrong.
- Sat Mar 13, 2021 9:44 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Oxidation and reduction
- Replies: 12
- Views: 1255
Re: Oxidation and reduction
Oxidation means that it loses electrons and is usually the anode. Reduction means that it gains electrons and is usually the cathode. This means that in your half-reactions you have to determine which one will give you a positive value since it is a galvanic cell and has to be spontaneous. Usually, ...
- Sat Mar 13, 2021 9:40 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Order of Cell Diagrams
- Replies: 2
- Views: 230
Re: Order of Cell Diagrams
I usually go from left to right. For example, Zn -> Zn^2+ + 2e- (oxidized) and Cu^2+ + 2e- -> Cu (reduced) so the order goes from left to right or farthest to closest Zn(s) I Zn^2+ (aq) II Cu^2+ (aq) I Cu (s) So Zn will become Zn^2+ when oxidized and Cu^2+ will become Cu when reduced. I hope this he...
- Sat Mar 13, 2021 9:35 pm
- Forum: Student Social/Study Group
- Topic: Sapling good to review for final?
- Replies: 16
- Views: 881
Re: Sapling good to review for final?
Yes, I agree that the textbook provides more questions that are similar to exams. However, Sapling is a very good place to practice questions about a topic and where it can give you detailed steps or explanations. Overall, I would do the textbook first and then Sapling.
- Sat Mar 13, 2021 7:48 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: E naught and K
- Replies: 3
- Views: 397
Re: E naught and K
I think if you have a large E naught then that means you must have a large K. I think it works also for very small E naughts, which would mean we have a similar small K value. Hope this helps!
- Sat Mar 13, 2021 7:45 pm
- Forum: General Science Questions
- Topic: Final Nerves and thoughts
- Replies: 11
- Views: 809
Re: Final Nerves and thoughts
I think after the chem final I might take a quick nap before beginning to study for my other assignments. After finals, I'm hoping to completely relax by watching lots of movies and shows before school starts again.
- Sat Mar 13, 2021 7:43 pm
- Forum: Student Social/Study Group
- Topic: Spring Quarter
- Replies: 60
- Views: 2944
Re: Spring Quarter
I'm taking Chem 14C next quarter!
- Sat Mar 13, 2021 7:42 pm
- Forum: Student Social/Study Group
- Topic: Final Jitters
- Replies: 457
- Views: 333850
Re: Final Jitters
I usually try to relax and do my usual routine. I wouldn't really do problems before my exam because I feel like that would mess me up more, but I would just check my notes quickly. Also, listening to music or again doing something you would normally do in the day calms me down a lot.
- Sat Mar 13, 2021 7:40 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Saying Thank You to Dr. Lavelle
- Replies: 490
- Views: 513036
Re: Saying Thank You to Dr. Lavelle
Thank you so much for all of the time that you put into teaching us chemistry, especially in a period of time where it may have been difficult to. Thank you for all of the resources and time that you gave so that we could understand all of the topics. I hope you continue to have fun teaching chemist...
- Sat Mar 13, 2021 2:53 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Chemistry Community Posts
- Replies: 10
- Views: 551
Chemistry Community Posts
Since Professor Lavelle won't be teaching Chem 14C, what will happen with our posts? Will they forever remain on this website and can we access it whenever we'd like? I know that there are some posts that are from years ago, so I was wondering how this would all work out. Thanks in advance!
- Sat Mar 13, 2021 2:51 pm
- Forum: Balancing Redox Reactions
- Topic: Acidic and Basic Redox Reactions
- Replies: 7
- Views: 570
Acidic and Basic Redox Reactions
Just to make sure I'm doing this correctly and efficiently, I will note down the steps that I take to solve these problems. Please let me know if something is wrong or missing and give me tips if you'd like to: Acidic Solutions: Recognize them because one reactant will have oxygen and the products w...
- Sat Mar 13, 2021 2:44 pm
- Forum: Student Social/Study Group
- Topic: How do you deal with burnout?
- Replies: 144
- Views: 13074
Re: How do you deal with burnout?
I usually make a schedule for the week and decide which day or days I would use to relax and not do a lot of homework or studying. It has really helped me not burn out or lose my motivation for days when I do need to work. I always recommend doing self-care days because your health will always matte...
- Tue Mar 09, 2021 11:27 pm
- Forum: Student Social/Study Group
- Topic: Clubs/Organizations
- Replies: 9
- Views: 618
Clubs/Organizations
I hope that all of you are doing well! I have a question about organizations and clubs. How many clubs are you involved in and how involved are you? I feel like quarantine is making it especially difficult to actually be a part of something.
- Tue Mar 09, 2021 11:20 pm
- Forum: Acidity & Basicity Constants and The Conjugate Seesaw
- Topic: Increasing/Decreasing pH and buffer solutions
- Replies: 4
- Views: 308
Increasing/Decreasing pH and buffer solutions
In Brooke's final review worksheet (3/8), there was a problem (#2) where it asks what would increase the pH of a buffer solution. What could we add/remove that would increase or decrease the pH of a solution in general? Thanks in advance!
- Tue Mar 09, 2021 11:15 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: What was your favorite chem topic?
- Replies: 137
- Views: 8545
Re: What was your favorite chem topic?
I really enjoyed doing chemical equilibrium and thermochemistry. I guess thermochemistry just made me realize how many things are related to it and how it all works. I still find it kind of hard to understand, but I really enjoy it!
- Tue Mar 09, 2021 11:10 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Galvanic/Voltaic Cells
- Replies: 1
- Views: 142
Galvanic/Voltaic Cells
I'm a little confused about what the answer would be for problems that are Galvanic cells and those that are not. If a problem states that it is Galvanic, would E cell always be positive? If it does not state that, would E cell always be negative? Thanks in advance!
- Tue Mar 09, 2021 11:07 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Exothermic vs. Endothermic
- Replies: 2
- Views: 408
Exothermic vs. Endothermic
Exothermic means that the delta G is going to be negative while endothermic means that the delta G will be positive. However, without any values to determine this, is the general rule that if a reaction is forming a product then it is exothermic (i.e. 3H2 + N2 -> 2NH3). Is it the same for endothermi...
- Tue Mar 09, 2021 11:03 pm
- Forum: Student Social/Study Group
- Topic: Balance / Self Care Tips
- Replies: 62
- Views: 2893
Re: Balance / Self Care Tips
Yeah, I understand how you feel. Before, I would spend every single day either studying for an upcoming exam or just catching up on assignments and homework without actually taking a break. This led to me burning out a lot more as the days went by until I started setting up a schedule to at least ha...
- Tue Mar 09, 2021 10:59 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: How to determine Cathode and Anode
- Replies: 3
- Views: 472
How to determine Cathode and Anode
On Brooke's final review worksheet (3/8), we had to calculate E naught. On the worksheet, it didn't mention which was a cathode or anode, so how would you determine which was which to solve the problem. Thanks in advance!
- Tue Mar 09, 2021 10:54 pm
- Forum: Student Social/Study Group
- Topic: Planning on dorming in the Fall?
- Replies: 61
- Views: 3122
Re: Planning on dorming in the Fall?
oh man i want to move into dorms in the fall! but does anyone know if it'll be only single dorms or if there's a chance to have doubles? (i'm pretty sure a single dorm would be a hefty cost for me but i think i might still try? not too sure lol) Yeah, I also want to move in, and I'm hoping that the...
- Tue Mar 09, 2021 10:52 pm
- Forum: Student Social/Study Group
- Topic: Culinary Chemistry
- Replies: 239
- Views: 31547
Re: Culinary Chemistry
I always found ceviche to be an interesting dish! It's essentially letting raw shrimp marinate in an acidic base (oxymoron haha) mainly composed of lemon or lime juice. The citric acid causes the proteins in the shrimp to go through denaturation, changing its physical and chemical properties so tha...
- Tue Mar 09, 2021 9:38 pm
- Forum: Student Social/Study Group
- Topic: What do you miss / What are you looking forward to?
- Replies: 92
- Views: 8083
Re: What do you miss / What are you looking forward to?
I'm a sophomore, and I miss the people in my residential house. It was nice to know everyone and have people to rely on for a lot of things. I guess it also adds to how I miss talking to people and the scenery on campus. I also really miss the events that would take place there.
- Tue Mar 09, 2021 9:35 pm
- Forum: Student Social/Study Group
- Topic: Fave food
- Replies: 266
- Views: 28526
Re: Fave food
I've been craving fast food these past few weeks!
- Tue Mar 09, 2021 9:33 pm
- Forum: Student Social/Study Group
- Topic: What organizations are you guys in?
- Replies: 53
- Views: 3005
Re: What organizations are you guys in?
At the moment, I am in PATHS!
- Tue Mar 09, 2021 9:32 pm
- Forum: Student Social/Study Group
- Topic: Fav Shows of the Moment
- Replies: 115
- Views: 26434
Re: Fav Shows of the Moment
I've been rewatching all of the seasons for Avatar. It's kind of nice because I remember watching this as a kid and there are moments where I'm once again surprised. It's like watching it for the first time again.
- Tue Mar 09, 2021 9:31 pm
- Forum: Student Social/Study Group
- Topic: How are y'all doing?
- Replies: 46
- Views: 2319
How are y'all doing?
Now that the winter quarter is almost ending, how have y'all been doing in terms of everyday feelings and motivation? It feels like every day in quarantine is the same, so what do you do to make every day the best?
- Tue Feb 16, 2021 9:25 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Textbook Example 4A.4 [ENDORSED]
- Replies: 1
- Views: 197
Textbook Example 4A.4 [ENDORSED]
"Neutralization reactions occurring when acids and bases are mixed can be very exothermic. Suppose you are investigating how the heat released in various neutralization reactions is related to the structures of certain acids. A constant-volume calorimeter was calibrated by carrying out a reacti...
- Tue Feb 16, 2021 7:16 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Systems and Examples
- Replies: 2
- Views: 211
Systems and Examples
Will we need to identify systems for the midterm? How will it affect the problem in the way we solve it? Do you have any examples or keywords necessary to identify/remember which system is which?
- Tue Feb 16, 2021 7:12 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: External Pressure and Vacuums [ENDORSED]
- Replies: 1
- Views: 117
External Pressure and Vacuums [ENDORSED]
In the textbook, it mentions that when external pressure is zero, then work is also zero because it is expanding into a vacuum. Are there any examples of this occurring?
- Tue Feb 16, 2021 7:09 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Lecture Question [ENDORSED]
- Replies: 1
- Views: 139
Lecture Question [ENDORSED]
In one of Lavelle's recent lectures, he mentions that our bodies give off heat because of our body's wasteful biological processes. Despite it being wasteful, is it more beneficial for us? Are there any consequences towards this?
- Thu Jan 28, 2021 3:29 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Standard States
- Replies: 2
- Views: 171
Standard States
Which molecules' standard states are we supposed to memorize for the midterm? It's H2(g), I2(s), Br2(l), C(s), Fe(s), but are there more that we're supposed to know?
- Thu Jan 28, 2021 3:14 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Approximations
- Replies: 1
- Views: 148
Approximations
I understand that when calculating x, we can sometimes approximate if K is larger than 1.0 x 10^3 or smaller than 1.0 x 10 ^-3, but do we only approximate if it's a large number (i.e. 1.0 x 10^-15 and 1.0 x 10^15)? Or can we still approximate if it is 1.0 x 10^4 / 1.0 x 10^-4?
- Thu Jan 28, 2021 3:08 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Acids and Bases List
- Replies: 4
- Views: 141
Acids and Bases List
How do you recognize when something is a strong acid/base or is neutral? Is there a list that we can use to memorize them and where can I find it?
- Tue Jan 26, 2021 6:46 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Topic 5H.3 Exercise
- Replies: 1
- Views: 92
Topic 5H.3 Exercise
The problem asks to determine the value of K using other chemical equations. Looking at the solutions book, I can see how it would work and where we would get the answer, but I'm still a little confused. Can someone please explain how they understood and got the answer to the problem? Thank you!
- Sun Jan 17, 2021 7:51 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Sapling Week 1 #10
- Replies: 7
- Views: 417
Sapling Week 1 #10
The question is asking for the equilibrium constants after adding 1.00 moles NO2. One of the questions asked about the equilibrium concentrations of N2O4 and NO2, and I had problems setting up the quadratic equation to solve for x. Can someone tell me the steps they took to solve it? Thank you in ad...
- Sun Jan 17, 2021 7:47 pm
- Forum: Student Social/Study Group
- Topic: Comfort Movies
- Replies: 168
- Views: 22287
Re: Comfort Movies
My comfort movie is Spirit: Stallion of the Cimarron. As a child, I loved watching this movie, and it's a miracle it isn't broken from the number of times I've watched this movie. It's a kid's movie, and it has an amazing soundtrack to listen to.
- Sun Jan 17, 2021 7:43 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: K < 10^-4
- Replies: 2
- Views: 122
Re: K < 10^-4
In most cases, K will be raised to a very large power (for example 2.0 x 10^-37). Because it is such a small number it won't necessarily make a big change when calculating for equilibrium or anything related. Without approximation, we would have to do difficult calculations. If K is greater than 10^...
- Sun Jan 17, 2021 7:34 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: ICE table troubles
- Replies: 16
- Views: 700
ICE table troubles
Hi everyone! I have certain problems with ICE tables. I understand how to use them and what I need to put in each part of the table, but there are moments where I mess up in small things. Any tips or advice on what to do on these occasions or what you always do to solve a problem?
- Sun Jan 17, 2021 7:32 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Sapling Homework #5
- Replies: 9
- Views: 343
Sapling Homework #5
Hi everyone! I had trouble with the problem that had multiple given equations to solve for K. I was able to solve the problem, but it took me a lot of tries and a lot of time. Can someone explain how they worked through the problem with the steps and what worked best for you in terms of how you solv...
- Thu Dec 17, 2020 12:21 am
- Forum: Student Social/Study Group
- Topic: Plans for Relaxing After Finals
- Replies: 98
- Views: 11386
Re: Plans for Relaxing After Finals
I plan to relax by watching shows, hanging out with my family, and starting up my self-care routine. Lately, I have not been doing it, and I think I'm definitely going to feel better after I start again.
- Thu Dec 17, 2020 12:19 am
- Forum: Student Social/Study Group
- Topic: Motivation
- Replies: 39
- Views: 1729
Motivation
How did you all stay motivated this quarter and what did you do to keep it up? I feel like this quarter just zapped my energy and motivation slowly as the quarter went on, and I want to be prepared for the next quarter.
- Thu Dec 17, 2020 12:17 am
- Forum: Student Social/Study Group
- Topic: Favorite TV shows
- Replies: 277
- Views: 34282
Re: Favorite TV shows
I would recommend Mindhunter. It's so good but sadly the third season is going to take a long time to come out. It left off on a huge cliffhanger the second season, so beware!
- Thu Dec 17, 2020 12:15 am
- Forum: Student Social/Study Group
- Topic: Study Habits
- Replies: 1
- Views: 138
Study Habits
For those who did very well on the 14A final, what were your study habits? What did you do to understand the topics, and how did you work through topics that were very difficult?
- Thu Dec 17, 2020 12:12 am
- Forum: Student Social/Study Group
- Topic: Winter Break Plans
- Replies: 45
- Views: 1924
Re: Winter Break Plans
That's so amazing! I miss traveling and seeing new places. For winter break, I'm most likely going to stay home and start my self-care routine again. Hope you have fun and stay safe!
- Thu Dec 17, 2020 12:06 am
- Forum: Lewis Acids & Bases
- Topic: Acid and Base theories
- Replies: 2
- Views: 210
Acid and Base theories
Can someone explain to me the difference between the theories regarding acids and bases (i.e. Bronsted-Lowry, Lewis, etc.)?
- Thu Dec 17, 2020 12:04 am
- Forum: Lewis Acids & Bases
- Topic: Strong Acids
- Replies: 1
- Views: 171
Strong Acids
In the lecture, professor Lavelle explained a strong acid is very electronegative. However, the textbook mentions that the greater the atomic radius is the stronger the acid will be (HF < HCl < HBr < HI). How is this possible if the bigger the atomic radius the less electronegative it will be. What ...
- Wed Dec 16, 2020 11:58 pm
- Forum: Amphoteric Compounds
- Topic: Amphoteric and Amphiprotic
- Replies: 2
- Views: 351
Amphoteric and Amphiprotic
What is the difference between amphoteric and amphiprotic?
- Wed Dec 16, 2020 11:57 pm
- Forum: Naming
- Topic: Naming Coordination Complexes
- Replies: 4
- Views: 378
Naming Coordination Complexes
Is there an easier way to name coordination complexes? Any tips or advice on learning the list?
- Mon Nov 30, 2020 12:00 am
- Forum: Hybridization
- Topic: Valence Bond Theory
- Replies: 2
- Views: 220
Valence Bond Theory
In the textbook, it explains how the valence bond theory calculates the probability of finding an electron in a certain location, but I don't understand how it would do that. Can someone explain what is connected to this theory and what it means?
- Sun Nov 29, 2020 11:56 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Experimental Bond Angles
- Replies: 2
- Views: 427
Experimental Bond Angles
In the textbook, it mentioned that there are some bond angles that are "fixed," which means that we will always know what they are if we know the shapes, but it also mentioned experimental bond angles. Will we have to know how to find these for the final? If so, how would we find it or kno...
- Sun Nov 29, 2020 11:54 pm
- Forum: Hybridization
- Topic: Hybrid Orbitals
- Replies: 7
- Views: 442
Hybrid Orbitals
I'm a little confused about what hybrid orbitals are and how to determine them. Can someone explain them to me?
- Sun Nov 29, 2020 11:52 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Rings and cyclic structures
- Replies: 2
- Views: 111
Rings and cyclic structures
There were some problems in Sapling where we had to make Lewis structures, but I am confused about some of the feedback I got on them. It mentioned that I needed to do ring or cyclic structures, but I'm not sure what they are. Can someone explain all the structures we need to know in order to do the...
- Sun Nov 29, 2020 11:49 pm
- Forum: Resonance Structures
- Topic: Stable Resonance Structures
- Replies: 4
- Views: 288
Stable Resonance Structures
What are all of the things that we need to take into account before determining which resonance structure is stable or not?
- Sun Nov 29, 2020 11:45 pm
- Forum: Bond Lengths & Energies
- Topic: London Dispersion Forces/ van der Waal forces
- Replies: 8
- Views: 678
London Dispersion Forces/ van der Waal forces
Is there a difference between London Dispersion Forces and van der Waals forces? If there isn't, would all interactions between molecules have LDF or does it only pertain to van der Waal forces?
- Sun Nov 29, 2020 11:43 pm
- Forum: Bond Lengths & Energies
- Topic: London Dispersion Forces
- Replies: 5
- Views: 285
London Dispersion Forces
Would having more bonded atoms make LDF interactions stronger? Why would that make it stronger?
- Sun Nov 29, 2020 11:39 pm
- Forum: Ionic & Covalent Bonds
- Topic: Polar and Nonpolar
- Replies: 37
- Views: 1676
Polar and Nonpolar
I usually know if a molecule is polar or nonpolar depending on if there is an unequal or equal sharing of electrons, but would I need to do more to make sure?
- Sun Nov 29, 2020 11:36 pm
- Forum: Resonance Structures
- Topic: Resonance Structure Confusion
- Replies: 5
- Views: 438
Resonance Structure Confusion
There was a problem on Sapling that asked if all three structures were resonance structures. Why are they not considered this?
- Sun Nov 29, 2020 11:30 pm
- Forum: Hybridization
- Topic: Delocalized Pi Bond
- Replies: 10
- Views: 769
Delocalized Pi Bond
In sapling, there was a question in regards to a delocalized pi bond. What is that, and how would you recognize it in an example?
- Sun Nov 29, 2020 11:29 pm
- Forum: Hybridization
- Topic: Determining the number of sigma and pi bonds
- Replies: 8
- Views: 885
Determining the number of sigma and pi bonds
In Sapling, they gave a question about how many sigma and pi bonds there were in a molecule? Would we have to count each time the number of sigma bonds in each bond and then move on towards counting the pi bonds?
- Sun Nov 29, 2020 11:27 pm
- Forum: Hybridization
- Topic: Sigma and Pi bonds
- Replies: 29
- Views: 2583
Sigma and Pi bonds
What are the differences between sigma and pi bonds and how can you recognize them in examples or pictures?
- Sun Nov 29, 2020 11:25 pm
- Forum: Hybridization
- Topic: Sapling Hybridization Problems
- Replies: 4
- Views: 273
Sapling Hybridization Problems
On Sapling, there were some questions about hybridization, and it gave a chart that said bonds and lone pairs determined the level. Is there a simpler way to do this, or can someone clear it up a little for me? Thank you in advance!
- Sun Nov 29, 2020 11:20 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Equatorial Lone Pair
- Replies: 1
- Views: 130
Equatorial Lone Pair
In the textbook, it explains that a lone pair that is equatorial has the lowest energy. What makes it have the lowest energy compared to an axial lone pair?
- Sun Nov 29, 2020 11:16 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Shape Names and Degrees
- Replies: 4
- Views: 298
Shape Names and Degrees
First, are there any tips on how to memorize the shape names? Second, will we need to memorize the degrees of the angles in the shapes for the midterms, and are there any tips on how to memorize them?
- Sun Nov 08, 2020 8:33 pm
- Forum: Resonance Structures
- Topic: Delocalized
- Replies: 5
- Views: 259
Delocalized
In the lecture, Lavelle explained what delocalized means, but could someone explain to me the importance of double bonds being delocalized? Also, why does is it important to draw the delocalized double bonds in multiple structures rather than only using one structure?
- Sun Nov 08, 2020 8:11 pm
- Forum: Resonance Structures
- Topic: Lewis Structure
- Replies: 5
- Views: 470
Lewis Structure
In the lecture (11/02), Professor Lavelle discusses how to do Lewis structures and how they should look like (double bonds and formal charges). What are all the steps needed to complete the Lewis structure? By this, I mean, would it not be enough to make sure all valence electrons are bonded or that...
- Sun Nov 08, 2020 7:05 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Pauli Exclusion Principle and Hund's Rule
- Replies: 4
- Views: 375
Pauli Exclusion Principle and Hund's Rule
In the lecture, Professor Lavelle explained the Pauli exclusion principle and Hund's rule, but I am still a little confused about it. Can someone please explain it to me?
- Sun Nov 08, 2020 6:39 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Cations and Anions
- Replies: 4
- Views: 165
Cations and Anions
In Lavelle's lecture about ionic and covalent bonds, he discussed how one side of the periodic table forms cations and the other forms anions. Why does this occur?
- Sun Nov 08, 2020 6:36 pm
- Forum: Trends in The Periodic Table
- Topic: Tips for learning the trends in the Periodic table
- Replies: 11
- Views: 632
Tips for learning the trends in the Periodic table
I was wondering if anyone can share tips on how to memorize the trends in the periodic table (i.e. atomic and ionic radii, etc). Thank you in advance!
- Sun Nov 01, 2020 9:49 pm
- Forum: DeBroglie Equation
- Topic: When to use de Broglie and what numbers to use
- Replies: 8
- Views: 409
When to use de Broglie and what numbers to use
In sapling, there are some problems where they give you the equation 3.29 x 10^15(1/n1^2 - 1/n2^2) and another identical one except they use 1.0974 as rydberg's constant. How would you know which one to use and what are the differences in both of these?
- Sun Nov 01, 2020 8:15 pm
- Forum: Properties of Light
- Topic: Sapling 19
- Replies: 6
- Views: 684
Re: Sapling 19
You would use the de Broglie equation. Because it is asking for the velocity of the particles, you would need to change it from lambda = h/(mv) to v = h/(m/lambda) to solve the problem.
- Sun Nov 01, 2020 8:12 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Quantum Number Memorizing tips
- Replies: 2
- Views: 585
Quantum Number Memorizing tips
The quantum numbers n,l, and m describe the energy, size, shape, and orientation of wave functions, and I understand how to use them to find the ground state and everything else involved. However, I still have trouble remembering what the rules are for each rule for the quantum number. For example, ...
- Sun Nov 01, 2020 3:04 pm
- Forum: Photoelectric Effect
- Topic: Sapling Problem #25
- Replies: 4
- Views: 202
Sapling Problem #25
"The E.coli bacterium is about 2.0 μm long. Suppose you want to study it using photons of that wavelength or electrons having that de Broglie wavelength. What is the energy Ephoton of the photon? What is the energy Eelectron of the electron?" Can someone help me solve the second part of th...
- Sun Oct 25, 2020 5:56 pm
- Forum: Student Social/Study Group
- Topic: Midterm and Compound Memorization
- Replies: 6
- Views: 353
Re: Midterm and Compound Memorization
I don't believe we'll have to memorize the molecular formula or mass of certain compounds from their name alone on the midterm. Dr. Lavelle will provide most of the information we need to know, and I think that in later chemistry classes we will need to but not right now. However, I would check in w...
- Sun Oct 25, 2020 5:46 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Electron Density Distribution
- Replies: 8
- Views: 374
Re: Electron Density Distribution
Do we need to be able to find the electron density or is it something that will be given in the problems? I don't believe we'll need to know exactly the electron density or be given it. For the first midterm, we just need to conceptually understand what Schrodinger's equation is and how it relates ...
- Sun Oct 25, 2020 3:29 pm
- Forum: *Shrodinger Equation
- Topic: Conceptual understanding of Shrodinger Equation
- Replies: 1
- Views: 194
Re: Conceptual understanding of Shrodinger Equation
Shrodinger's Equation deals with the probability of finding electrons in certain areas of orbitals. For example, the s-orbital is a sphere. When calculating the probability of finding an electron, there will be an equal probability of finding e- anywhere in the s-orbital sphere. However, the p-orbit...
- Sun Oct 25, 2020 2:39 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Amplitude
- Replies: 16
- Views: 669
Re: Amplitude
Amplitude is equal to the intensity and brightness of a light. It would have no effect on wavelength and frequency at all because it would only be changing the height and would not be making it smaller or longer.
- Sun Oct 25, 2020 2:34 pm
- Forum: SI Units, Unit Conversions
- Topic: Other conversions for the Midterm
- Replies: 4
- Views: 337
Other conversions for the Midterm
The constants and equations paper that Professor Lavelle provides for us has some of the conversions we need but are there others that we need to know? For example, we have the conversions for nanometers, picometers, kilograms to grams, and a few others, but are there some we need to know to solve o...
- Sun Oct 25, 2020 2:31 pm
- Forum: Properties of Electrons
- Topic: Balmer and Lyman Series
- Replies: 3
- Views: 180
Balmer and Lyman Series
Can someone explain the difference between the Balmer and Lyman series and how you would identify them? There are some problems in the textbook that have the Lyman series, but I'm not sure how you would recognize it and how you would use that information to solve the problem. Also, would the midterm...
- Sun Oct 18, 2020 5:09 pm
- Forum: Photoelectric Effect
- Topic: Photoelectric Effect Module Question 28
- Replies: 9
- Views: 373
Re: Photoelectric Effect Module Question 28
Jaden Haskins 2F wrote:OH this is a response to my last question and it might be silly but all electrons have the same mass correct? It doesn't differ based on the element?
All electrons share the same mass, so it will always be 9.10956 x 10^-31 kg.
- Sun Oct 18, 2020 5:07 pm
- Forum: Properties of Light
- Topic: Photoelectric effect Problem Audio Visual Topics Q28
- Replies: 4
- Views: 169
Re: Photoelectric effect Problem Audio Visual Topics Q28
This is how I answered those questions: a) I used the equation 1/2mv^2. In this equation, m = 9.10956 x 10^-31 (the mass of an electron) and v = 6.61 x 10^5. The equation would look something like this 1/2(9.10956 x 10^-31) x (6.61 x 10^5) which equals the kinetic energy of the ejected electron. b) ...
- Sun Oct 18, 2020 4:51 pm
- Forum: Balancing Chemical Reactions
- Topic: Balancing Chemical Equations
- Replies: 11
- Views: 549
Re: Balancing Chemical Equations
Because there are no parentheses around CO4, this just means that they are being counted separately. By this, I mean that C = 1 and O = 4. If it was (CO4)^2, then that would mean you would multiply each element with 2, becoming C = 2 and O = 8.
- Sun Oct 18, 2020 4:45 pm
- Forum: Balancing Chemical Reactions
- Topic: Balancing Chemical Reactions Order
- Replies: 49
- Views: 5595
Re: Balancing Chemical Reactions Order
There really isn't an order as to how to balance equations. I find it easier to separate them into a table with products on one side and reactants on the other. This just helps in figuring out which element would be the best to start with first. However, there are some times where I find that I need...
- Sun Oct 18, 2020 4:39 pm
- Forum: Balancing Chemical Reactions
- Topic: Mixed Numbers
- Replies: 7
- Views: 332
Re: Mixed Numbers
You shouldn't have a balanced equation with mixed numbers. Usually, if you do have a mixed number (6.5), you would divide the entire equation (both products and reactants) to get rid of the mixed number. In the end, you would have whole numbers in the equation, which makes everything much easier to ...
- Sat Oct 10, 2020 5:36 pm
- Forum: Empirical & Molecular Formulas
- Topic: Sapling Homework 1 Q#9
- Replies: 21
- Views: 779
Re: Sapling Homework 1 Q#9
So this is how I solved the problem: 1. To find the grams for C, you have to use the molar mass of C (12.01 g/mol) and the mass of the compound CO2 (44.01 g). You would divide the molar mass of C by the compound mass (C/CO2). This gives you the grams for C. 2. To find the grams for H, you would do t...
- Sat Oct 10, 2020 5:21 pm
- Forum: Empirical & Molecular Formulas
- Topic: Sapling Hw Week 1 #10
- Replies: 20
- Views: 588
Re: Sapling Hw Week 1 #10
Javier Perez M 2J wrote:Was this chemical reaction balanced already or did we have to balance it? The one provided in the question
The chemical reaction that was provided was balanced already, so you did not have to balance it.
- Sat Oct 10, 2020 5:18 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: sapling hw #7
- Replies: 17
- Views: 620
Re: sapling hw #7
After reading some of the replies, I'm afraid I have a silly question. People are saying to "multiply 0.325 with 590.1g" but my question is what they did to get 0.325 and why. Thank you! They got .325 from the percentage of calcium chloride (32.5%). You would move the decimal point on the...
- Sat Oct 10, 2020 5:12 pm
- Forum: Empirical & Molecular Formulas
- Topic: Sapling Hw 1 #10
- Replies: 5
- Views: 132
Re: Sapling Hw 1 #10
The formula for 2-butanone is C4H8O, and you would calculate the molar mass in order to find the moles. You would then assume from the picture that it is a 1:1 ratio and that the moles would be the same for both 2-butanone and 3-methyl-3-hexanol.