Search found 115 matches
- Sun Mar 14, 2021 10:21 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Salt Bridges
- Replies: 4
- Views: 460
Re: Salt Bridges
Salt bridges are represented by a double solid line like this II
- Sun Mar 14, 2021 10:20 pm
- Forum: Student Social/Study Group
- Topic: On Campus class vs. remote
- Replies: 21
- Views: 1501
Re: On Campus class vs. remote
I think a lot of classes will hopefully be in person. Some of the larger lectures might still be remote though unfortunately.
- Sun Mar 14, 2021 10:19 pm
- Forum: Student Social/Study Group
- Topic: Note Taking
- Replies: 145
- Views: 17276
Re: Note Taking
I use handwritten notes!
- Sat Mar 13, 2021 12:11 pm
- Forum: Student Social/Study Group
- Topic: Electrochemistry Notes
- Replies: 1
- Views: 179
Re: Electrochemistry Notes
These are amazing thank you so much for sharing!
- Fri Mar 12, 2021 8:55 am
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Intermediates
- Replies: 6
- Views: 356
Re: Intermediates
Correct! Intermediates will never appear in the rate law. However, I believe it is possible for catalysts to appear in the rate law.
- Fri Mar 12, 2021 8:52 am
- Forum: General Rate Laws
- Topic: Sapling #5
- Replies: 8
- Views: 461
Re: Sapling #5
Hi! For this one you can just pick a value of 1 for A and B and see what happens to each. For example, if the first-order reaction of A is halved, the reaction rate will change by a factor of (1/2)^1. If the second-order reaction of B is tripled, B will change by a factor of (3)^2. This means that y...
- Fri Mar 12, 2021 8:48 am
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: 6M.3 Textbook Why cant we add the half reactions?
- Replies: 3
- Views: 266
Re: 6M.3 Textbook Why cant we add the half reactions?
Hi! I think if you use your method but make sure to flip the same reaction, you should get the same answer!
- Thu Mar 11, 2021 8:58 am
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Units for Activation Energy
- Replies: 28
- Views: 2007
Re: Units for Activation Energy
kJ /mol !
- Thu Mar 11, 2021 8:58 am
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: Calculating n
- Replies: 17
- Views: 1028
Re: Calculating n
One you've balanced the half reactions you just have to look at how many electrons ended up being transferred. That number will be your n value!
- Thu Mar 11, 2021 8:57 am
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Textbook 4E9 Help
- Replies: 2
- Views: 326
Re: Textbook 4E9 Help
Hi! This question is basically asking about the stability of benzene as a resonance structure versus the stability in terms of just double bonds and single bonds. The bond enthalpy for a carbon carbon bond in resonance structures is a different value than a C-C double bond or single bond. The proble...
- Sun Mar 07, 2021 11:00 am
- Forum: General Rate Laws
- Topic: Youtube Review
- Replies: 17
- Views: 1002
Re: Youtube Review
Organic chemistry tutor has definitely been a life saver.
- Sun Mar 07, 2021 10:59 am
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Concentration Cells at Equilibrium
- Replies: 7
- Views: 395
Re: Concentration Cells at Equilibrium
Hi! Concentration cells are not always at equilibrium. Basically, the cell is working to dilute the more concentrated cell, and concentrate the more diluted cell until it reaches equilibrium, which creates a voltage.
- Sun Mar 07, 2021 10:57 am
- Forum: Zero Order Reactions
- Topic: Half-life equations
- Replies: 3
- Views: 194
Re: Half-life equations
Hi! Adding on to the post above, it depends on whether each equation is dependent on initial concentration or not. This is obtained from the integrated rate law.
- Sun Mar 07, 2021 10:56 am
- Forum: Balancing Redox Reactions
- Topic: Balancing Reactions Help
- Replies: 5
- Views: 328
Re: Balancing Reactions Help
Hi! The textbook has a really good explanation on how to do it. I would also recommend going to a UA session if you're still unsure and asking them to help explain it!
- Sun Mar 07, 2021 10:55 am
- Forum: Zero Order Reactions
- Topic: Overall order of the reaction
- Replies: 45
- Views: 2068
Re: Overall order of the reaction
The overall order is determined by adding up the orders of all the elementary reactions!
- Sun Feb 28, 2021 10:23 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Sapling # 9
- Replies: 2
- Views: 246
Re: Sapling # 9
Hi! Your half reactions are going to be Zn2+(aq) + 2e– → Zn(s) and Au3+(aq) + 3e– → Au(s).
- Sun Feb 28, 2021 10:21 pm
- Forum: Balancing Redox Reactions
- Topic: Sapling week 7/8 #3
- Replies: 3
- Views: 254
Re: Sapling week 7/8 #3
Hi! When you're balancing reactions in basic conditions, the process is a little different. First you need to split the reaction into the half reactions. Then for each reaction, you balance all the oxygens by using H2O. Then, you balance the hydrogens by using water, and how many ever waters you add...
- Fri Feb 26, 2021 12:15 am
- Forum: Balancing Redox Reactions
- Topic: Balancing Redox Method
- Replies: 2
- Views: 208
Re: Balancing Redox Method
Hi! You can only add H+ if the problem states that it's occurring in acidic conditions. If this is the case, you will first use H2O to balance the oxygens, and then use H+ to balance the hydrogens. For the second question, you always add electrons in order to balance the charges. Once you find the c...
- Wed Feb 24, 2021 4:50 pm
- Forum: Balancing Redox Reactions
- Topic: Sapling Glitch?
- Replies: 8
- Views: 491
Re: Sapling Glitch?
This happened to me as, well but when I logged out and refreshed everything it worked for me again!
- Wed Feb 24, 2021 12:11 am
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: W(max) = delta G
- Replies: 3
- Views: 264
Re: W(max) = delta G
I believe by definition G is the maximum amount of non-expansion work that can be done at constant temperature and pressure!
- Wed Feb 24, 2021 12:08 am
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Where do I put Pt?
- Replies: 7
- Views: 621
Re: Where do I put Pt?
Hi! You put Pt on any side that is missing a conducting solid, so that it can act as one!
- Sun Feb 21, 2021 7:11 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: C vs Cs/Cm
- Replies: 8
- Views: 1719
Re: C vs Cs/Cm
Molar heat capacity refers to the number of moles, and specific heat capacity refers to the mass in grams!
- Sun Feb 21, 2021 7:09 pm
- Forum: Balancing Redox Reactions
- Topic: Oxidation States for TM
- Replies: 6
- Views: 355
Re: Oxidation States for TM
Hi! TM oxidation numbers need to be calculated based on the other elements in the compound!
- Sun Feb 21, 2021 7:08 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: 4J.5 Standard change in gibbs free energy
- Replies: 6
- Views: 402
Re: 4J.5 Standard change in gibbs free energy
I think it's just a way to confirm that we know how to calculate it in a few different ways!
- Thu Feb 18, 2021 3:50 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Textbook 4I.5
- Replies: 5
- Views: 414
Re: Textbook 4I.5
Hi! Here is my work to go along with the steps that previous people have posted. Hope this helps!
- Thu Feb 18, 2021 3:48 pm
- Forum: Phase Changes & Related Calculations
- Topic: Focus 4.5 10 hrs versus 10.5 hours
- Replies: 4
- Views: 342
Re: Focus 4.5 10 hrs versus 10.5 hours
Hi! Basically, we know that the water took 30 min to get to the final temperature. That means that once the ice has turned into the initial temperature of the water, it will also take 30 min to reach the temperature. Therefore, we only consider the time it took for the ice to actually turn to water ...
- Thu Feb 18, 2021 3:46 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Textbook Question 4A.7
- Replies: 4
- Views: 460
Re: Textbook Question 4A.7
Hi! The steps that everyone has posted are correct, and here is my work to hopefully clarify more!
- Sun Feb 14, 2021 4:15 pm
- Forum: Calculating Work of Expansion
- Topic: Textbook Problem 4B.13
- Replies: 6
- Views: 459
Re: Textbook Problem 4B.13
Hi! Here's my work for this problem - hope it helps!
- Sat Feb 13, 2021 1:00 am
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Sapling 4I.5
- Replies: 2
- Views: 207
Re: Sapling 4I.5
Hi! All the molar heat capacities will either be given in the problem, or available to reference on the constant & equations sheet.
- Thu Feb 11, 2021 10:01 am
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Kelvin conversion
- Replies: 40
- Views: 3406
Re: Kelvin conversion
Hi! You just have to add 273.15 to your C value to get Kelvin! It's on your equation sheet as well :)
- Wed Feb 10, 2021 5:18 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Master Equations and Units Post
- Replies: 1
- Views: 102
Re: Master Equations and Units Post
Yes!!
I started a document with some of the equations and it's in the shared google drive. Anyone can add to it with any more equations we've learned! :))
https://drive.google.com/drive/folders/1-iUlSUXyOWLHC5chqYRLC2ODsKNCF5fe
I started a document with some of the equations and it's in the shared google drive. Anyone can add to it with any more equations we've learned! :))
https://drive.google.com/drive/folders/1-iUlSUXyOWLHC5chqYRLC2ODsKNCF5fe
- Wed Feb 10, 2021 12:02 am
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Textbook Problem 4.7: Standard Enthalpies of Formation
- Replies: 3
- Views: 309
Re: Textbook Problem 4.7: Standard Enthalpies of Formation
Hi!
I believe your value for the enthalpy of formation for water should be -285.83!
I believe your value for the enthalpy of formation for water should be -285.83!
- Tue Feb 09, 2021 12:23 am
- Forum: Calculating Work of Expansion
- Topic: Textbook problem 4B.13
- Replies: 6
- Views: 315
Re: Textbook problem 4B.13
Hi! Yes, for this equation for work, the P is referring to external pressure.
- Fri Feb 05, 2021 4:04 pm
- Forum: Ideal Gases
- Topic: Gas Constant Value
- Replies: 43
- Views: 1737
Re: Gas Constant Value
Hi! It all depends on what is given in the problem. Usually the first thing I look at is the units of pressure. If there is no pressure given, I will go with the R value that has no pressure in the units!
- Fri Feb 05, 2021 4:02 pm
- Forum: Student Social/Study Group
- Topic: Sapling HW and exams
- Replies: 19
- Views: 839
Re: Sapling HW and exams
I definitely think studying the Sapling questions are a good tool for exams. After you complete the problem it gives you a detailed explanation how they got to the answer that can help aid your understanding as well!
- Fri Feb 05, 2021 3:59 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Textbook Problem 4A.13
- Replies: 3
- Views: 218
Re: Textbook Problem 4A.13
Hi! Here's how I worked it out.
Hope this helps!
Hope this helps!
- Fri Feb 05, 2021 3:53 pm
- Forum: Student Social/Study Group
- Topic: Study routine.
- Replies: 51
- Views: 2708
Re: Study routine.
Hi! I definitely think that, as boring as it might be at times, reading the textbook really has been the most helpful thing for me. There are a lot of great explanations in there! UA sessions are also extremely helpful with further explanations.
- Fri Feb 05, 2021 3:52 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Constant pressure/ volume
- Replies: 11
- Views: 492
Re: Constant pressure/ volume
Hi! If one is constant that does not automatically mean the other is constant. You will have to look at the information explicitly stated in the problem.
- Tue Feb 02, 2021 10:53 am
- Forum: Administrative Questions and Class Announcements
- Topic: Weeks 3 and 4 Sapling HW
- Replies: 5
- Views: 312
Re: Weeks 3 and 4 Sapling HW
Hi! The homework is due this Sunday. If it says 65% that just means you've completed 65% of the assignment!
- Tue Feb 02, 2021 10:52 am
- Forum: Calculating Work of Expansion
- Topic: different R constants
- Replies: 7
- Views: 419
Re: different R constants
Hi! You can always tell which R constant to use based on the units. If you match up the units given in the problem to the R constant, most (if not all) of the units should cancel out!
- Sun Jan 31, 2021 10:53 pm
- Forum: Calculating Work of Expansion
- Topic: why expanding volume has negative work
- Replies: 6
- Views: 401
Re: why expanding volume has negative work
Hi! Because a system has to do work in order for expansion to occur, it is losing a certain amount of energy to do this work. That's why the w would have a negative sign!
- Sun Jan 31, 2021 10:42 pm
- Forum: Ideal Gases
- Topic: Reversing Reactions
- Replies: 68
- Views: 2538
Re: Reversing Reactions
Hi! When you reverse a reaction, K becomes the reciprocal, so you would calculate 1/K.
- Thu Jan 28, 2021 4:29 pm
- Forum: Administrative Questions and Class Announcements
- Topic: HW Due Date
- Replies: 15
- Views: 705
Re: HW Due Date
Hi!
Homework is due this coming Sunday. Using hints from Sapling doesn't take any points off so that's definitely a good resource as well as the textbook! Good luck on the midterm!
Homework is due this coming Sunday. Using hints from Sapling doesn't take any points off so that's definitely a good resource as well as the textbook! Good luck on the midterm!
- Tue Jan 26, 2021 10:43 am
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Textbook Excercise 4D.15
- Replies: 3
- Views: 221
Re: Textbook Excercise 4D.15
Hi! Here is the work I did for 15. Hope this helps!
- Mon Jan 25, 2021 7:55 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: percentage ionization
- Replies: 2
- Views: 81
Re: percentage ionization
Hi!
This will work for your weak acid calculations.
This will work for your weak acid calculations.
- Fri Jan 22, 2021 11:00 am
- Forum: Administrative Questions and Class Announcements
- Topic: Textbook Solutions Not Appearing
- Replies: 7
- Views: 241
Re: Textbook Solutions Not Appearing
Hi!
This has happened to me before, so I use the pdf version of the solution manual! If you go on the sapling page and click on the link that says Atkins, it's a pdf file and that always works. The solutions also have more detailed explanations on how they got to the answer so it's super helpful!
This has happened to me before, so I use the pdf version of the solution manual! If you go on the sapling page and click on the link that says Atkins, it's a pdf file and that always works. The solutions also have more detailed explanations on how they got to the answer so it's super helpful!
- Thu Jan 21, 2021 8:39 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Midterm 1: Lecture cutoff
- Replies: 8
- Views: 328
Re: Midterm 1: Lecture cutoff
Hi!
I remember hearing that tomorrow will be the cutoff for the midterm 1 material. I'm sure next weeks information will be useful, but not necessary for this midterm!
I remember hearing that tomorrow will be the cutoff for the midterm 1 material. I'm sure next weeks information will be useful, but not necessary for this midterm!
- Wed Jan 20, 2021 11:18 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Midterm 1
- Replies: 9
- Views: 462
Re: Midterm 1
Hi! There's an updated constants & equations sheet on his website and I would have the period table as well!
- Tue Jan 19, 2021 11:31 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Approximately x
- Replies: 18
- Views: 705
Re: Approximately x
Hi! The general rule of thumb is if it is smaller than 10^-4. If you think it's safe to assume that x is 0, but aren't sure, you can always calculate the percent ionization (which is (concentration/initial concentration)(100%)) after you find the concentrations. If the percent ionization is less tha...
- Fri Jan 15, 2021 12:40 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Discussion section for Week 3
- Replies: 2
- Views: 127
Re: Discussion section for Week 3
Hi!
Discussion sections still take place unless yours is this coming Monday.
Discussion sections still take place unless yours is this coming Monday.
- Thu Jan 14, 2021 12:18 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Using net ionic equations
- Replies: 2
- Views: 111
Re: Using net ionic equations
Hi!
I don't think we have to worry about that for this unit at least. One of the UAs went over it in their session, but it isn't super relevant for now.
I don't think we have to worry about that for this unit at least. One of the UAs went over it in their session, but it isn't super relevant for now.
- Wed Jan 13, 2021 12:26 pm
- Forum: Student Social/Study Group
- Topic: Weekly Assignments
- Replies: 5
- Views: 241
Re: Weekly Assignments
The only things that are graded in this class are chem community, Sapling, and the exams! Everything else is just for your benefit.
- Tue Jan 12, 2021 12:00 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: 5I.7
- Replies: 4
- Views: 240
Re: 5I.7
Hi!
In terms of solving the problem, I would probably agree with the people that have already posted. But on a side note, #7 actually isn't in the list of problems he assigned us to do so we might not even be expected to know this exact problem!
In terms of solving the problem, I would probably agree with the people that have already posted. But on a side note, #7 actually isn't in the list of problems he assigned us to do so we might not even be expected to know this exact problem!
- Mon Jan 11, 2021 10:58 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Getting a negative during quadratic
- Replies: 5
- Views: 242
Re: Getting a negative during quadratic
Hi!
I would imagine that that was probably a calculation error. I think the numbers on sapling are different for everybody, but at least for mine, I didn't end up getting any negatives under the root!
I would imagine that that was probably a calculation error. I think the numbers on sapling are different for everybody, but at least for mine, I didn't end up getting any negatives under the root!
- Sun Jan 10, 2021 5:39 pm
- Forum: General Science Questions
- Topic: material
- Replies: 4
- Views: 276
Re: material
Hi!
I think Dr. Lavelle mentioned during lecture that not too many concepts from 14A would carry over. I've heard 14B has more calculations!
I think Dr. Lavelle mentioned during lecture that not too many concepts from 14A would carry over. I've heard 14B has more calculations!
- Thu Jan 07, 2021 12:42 pm
- Forum: General Science Questions
- Topic: mole vs. M
- Replies: 16
- Views: 3163
Re: mole vs. M
Hi!
M refers to molarity which is the same thing as mol/L
M refers to molarity which is the same thing as mol/L
- Wed Jan 06, 2021 11:44 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Quadratic Equations
- Replies: 7
- Views: 369
Re: Quadratic Equations
Hi!
If you get 2 positive numbers, you should omit the one that is larger than any of the given initial conditions. Generally, you will use the smaller positive number.
If you get 2 positive numbers, you should omit the one that is larger than any of the given initial conditions. Generally, you will use the smaller positive number.
- Wed Jan 06, 2021 11:41 am
- Forum: Administrative Questions and Class Announcements
- Topic: Sapling access issue
- Replies: 5
- Views: 227
Re: Sapling access issue
Hi!
You need to access Sapling through CCLE in order for it to work. In terms of the code, if you purchased multi-term access, they should have sent you 2 codes (one that you can enter for this quarter).
You need to access Sapling through CCLE in order for it to work. In terms of the code, if you purchased multi-term access, they should have sent you 2 codes (one that you can enter for this quarter).
- Wed Jan 06, 2021 11:38 am
- Forum: Administrative Questions and Class Announcements
- Topic: Audio-Visual focus modules
- Replies: 6
- Views: 360
Re: Audio-Visual focus modules
Hi!
During 14A, they were only posted for the first unit. I'm assuming this it just because of time and because Dr. Lavelle is giving us a chance to get ahead before the quarter starts.
During 14A, they were only posted for the first unit. I'm assuming this it just because of time and because Dr. Lavelle is giving us a chance to get ahead before the quarter starts.
- Tue Dec 15, 2020 10:32 am
- Forum: Student Social/Study Group
- Topic: Changing Study Habits
- Replies: 35
- Views: 1483
Re: Changing Study Habits
Definitely something that worked for me this quarter was going to all the UA sessions, so that's one thing I will continue next quarter! Also like you said, utilizing the textbook and reading all the information there :)
- Sat Dec 12, 2020 12:05 am
- Forum: Amphoteric Compounds
- Topic: Tricks for Determining
- Replies: 5
- Views: 420
Re: Tricks for Determining
Hi! A simple way to look at the trend is that metalloid band plus a few more atoms around it will form amphoteric compounds. If it's difficult to tell based on this, you will need to look at if it can accept as well as donate a proton.
- Sat Dec 12, 2020 12:02 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: H20
- Replies: 6
- Views: 608
Re: H20
Hi! Only one of the lone pairs can bond to a central atom.
- Fri Dec 11, 2020 11:46 pm
- Forum: Electronegativity
- Topic: Be vs Cl
- Replies: 49
- Views: 2957
Re: Be vs Cl
Hi! Electronegativity increases up and to the right. Therefore, Cl will be higher. Also, electronegativity refers to the atom's tendency to attract electrons. Since Cl has 7 valence electrons, it really wants to attract one to complete its octet. This means electronegativity will be higher.
- Fri Dec 11, 2020 11:41 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: 6f orbital
- Replies: 3
- Views: 2181
Re: 6f orbital
Hi!
This is possible because when the principle quantum number is n=6, all the l values can be 0-5. l=3 means the f subshell, which is where you would get the 6f.
This is possible because when the principle quantum number is n=6, all the l values can be 0-5. l=3 means the f subshell, which is where you would get the 6f.
- Fri Dec 11, 2020 11:37 pm
- Forum: Octet Exceptions
- Topic: Octet Exceptions and Expanded Octet Calculation
- Replies: 3
- Views: 549
Re: Octet Exceptions and Expanded Octet Calculation
Hi!
The main elements we definitely have to know for this class are P, S, and Cl. Other than that, anything with a d-orbital can have an expanded valence.
The main elements we definitely have to know for this class are P, S, and Cl. Other than that, anything with a d-orbital can have an expanded valence.
- Thu Dec 03, 2020 10:40 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Finding Coordination Number
- Replies: 14
- Views: 659
Re: Finding Coordination Number
The coordination number just refers to the number of points at which ligands are attached to the central metal atom!
- Thu Dec 03, 2020 10:36 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Chelates and Polydentates
- Replies: 2
- Views: 142
Re: Chelates and Polydentates
Hi! Everything with polydentate ligands is considered a chelating compound.
- Thu Dec 03, 2020 10:35 pm
- Forum: Hybridization
- Topic: pcl3
- Replies: 8
- Views: 827
Re: pcl3
The hybridization is sp3 because there are 4 regions of electron density (3 bonding pairs and 1 lone pair). 4 regions of electron density corresponds to sp3 hybridization.
- Thu Dec 03, 2020 10:33 pm
- Forum: Hybridization
- Topic: 2.45 b Textbook problem
- Replies: 3
- Views: 157
Re: 2.45 b Textbook problem
Hi! The composition of the bonds would be the bond all together. So for example in this structure, there's a C single bonded to an H. The composition of this bond would be sigma(H1s, 2Csp2) because the carbon has 3 regions of electron density. The lone pair is strictly referring to that lone pair. S...
- Thu Dec 03, 2020 10:29 pm
- Forum: Naming
- Topic: Sapling 9 #1
- Replies: 7
- Views: 334
Re: Sapling 9 #1
Hi!
The name of the compound should be pentaamminechlorocobalt(III) chloride.
The name of the compound should be pentaamminechlorocobalt(III) chloride.
- Thu Dec 03, 2020 10:27 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Difference between electron geometry and molecular geometry
- Replies: 12
- Views: 5834
Re: Difference between electron geometry and molecular geometry
Hi!
Electronic geometry takes into account all the bonding pairs as well as lone pairs on the central atom. molecular geometry only looks at the bonding pairs.
Electronic geometry takes into account all the bonding pairs as well as lone pairs on the central atom. molecular geometry only looks at the bonding pairs.
- Sun Nov 29, 2020 7:59 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: sigma vs pi bonds
- Replies: 33
- Views: 2157
Re: sigma vs pi bonds
Hi! Single bonds are always sigma bonds. Double bonds have 1 sigma and 1 pi, and triple bonds have 1 sigma and 2 pi
- Sun Nov 29, 2020 7:57 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Molecular Shape
- Replies: 12
- Views: 595
Re: Molecular Shape
Hi! yes, lone pairs affect both electronic arrangement and molecular shape.
- Tue Nov 24, 2020 5:16 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Midterm 2 Scores
- Replies: 9
- Views: 460
Re: Midterm 2 Scores
abby hyman wrote:Does anyone know if there is any way to review the ones you missed on midterm 2?
If you email your TA or go to office hours, they can discuss the ones you missed!
- Tue Nov 24, 2020 5:14 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Midterm 2 Results
- Replies: 10
- Views: 496
Re: Midterm 2 Results
The scores have been posted on ccle!
- Mon Nov 23, 2020 4:24 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Midterm 2 Grades Chem 14A
- Replies: 6
- Views: 451
Re: Midterm 2 Grades Chem 14A
I heard that there is a possibility grades will be released tomorrow! Either way, he will send out an email when they are posted :)
- Sun Nov 22, 2020 8:49 pm
- Forum: Ionic & Covalent Bonds
- Topic: Polar/ Nonpolar
- Replies: 25
- Views: 1339
Re: Polar/ Nonpolar
Hi!
You can use shape as a good indicator as to whether a molecule is polar or nonpolar. I would say that you still need to check whether or not the dipole moments cancel, but shape is a good check as well.
You can use shape as a good indicator as to whether a molecule is polar or nonpolar. I would say that you still need to check whether or not the dipole moments cancel, but shape is a good check as well.
- Sun Nov 22, 2020 8:48 pm
- Forum: Ionic & Covalent Bonds
- Topic: Radicals
- Replies: 10
- Views: 456
Re: Radicals
Hi!
Any time there's an uneven number of electrons it's a radical, so as others have said I would assume it's an error on the textbook's part.
Any time there's an uneven number of electrons it's a radical, so as others have said I would assume it's an error on the textbook's part.
- Sun Nov 22, 2020 8:46 pm
- Forum: Lewis Structures
- Topic: Electron Density
- Replies: 14
- Views: 655
Re: Electron Density
Hi!
Electron density refers to the probability that you will find an electron in that region.
Electron density refers to the probability that you will find an electron in that region.
- Tue Nov 17, 2020 11:38 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: n=6,l=5
- Replies: 7
- Views: 3223
Re: n=6,l=5
Hi!
l=5 would be a valid answer. Your l value can be all the number leading up to n-1. so for example, if n=5, all your possible l values would be 0,1,2,3,4.
l=5 would be a valid answer. Your l value can be all the number leading up to n-1. so for example, if n=5, all your possible l values would be 0,1,2,3,4.
- Tue Nov 17, 2020 11:36 pm
- Forum: Student Social/Study Group
- Topic: Midterm 2
- Replies: 19
- Views: 1053
Re: Midterm 2
Hi!
Definitely going to as many UA sessions has been the most helpful for me. Other than that, the textbook problems/sections are very helpful.
Definitely going to as many UA sessions has been the most helpful for me. Other than that, the textbook problems/sections are very helpful.
- Sat Nov 14, 2020 11:49 am
- Forum: Resonance Structures
- Topic: Delocalized Electrons
- Replies: 7
- Views: 372
Re: Delocalized Electrons
Hi!
Simply put, electrons that are delocalized are shared between atoms. Because resonance structures are a blend of all the possible lewis structures, this means that on a diagram, you can find these electrons in any position.
Simply put, electrons that are delocalized are shared between atoms. Because resonance structures are a blend of all the possible lewis structures, this means that on a diagram, you can find these electrons in any position.
- Sat Nov 14, 2020 11:47 am
- Forum: Student Social/Study Group
- Topic: Midterm 2
- Replies: 31
- Views: 1396
Re: Midterm 2
Hi!
The midterm will cover the last 8 bullets of outline 2 as well as all of outline 3.
The midterm will cover the last 8 bullets of outline 2 as well as all of outline 3.
- Sat Nov 14, 2020 11:46 am
- Forum: Polarisability of Anions, The Polarizing Power of Cations
- Topic: Polarizability
- Replies: 9
- Views: 751
Re: Polarizability
Hi! Basically,atoms or ions with electron clouds that readily undergo a large distortion are highly polarizable. Because of this principle, anions that are large can expect to be highly polarizable. This is because the anion is so large, that the nucleus only has weak control over its outermost elec...
- Sat Nov 14, 2020 11:42 am
- Forum: Trends in The Periodic Table
- Topic: N 3- vs S 2-
- Replies: 4
- Views: 263
Re: N 3- vs S 2-
Hi!
I don't think it has a huge affect so I believe nitrogen will still be smaller.
I don't think it has a huge affect so I believe nitrogen will still be smaller.
- Sat Nov 14, 2020 11:41 am
- Forum: Dipole Moments
- Topic: Textbook discrepancy
- Replies: 6
- Views: 305
Re: Textbook discrepancy
Hi! I was wondering this also. The textbook did mention that the arrow pointing towards the partial positive atom is a modern notation, and the arrow pointing towards the partial negative atom is older. Since the example he did in class has it pointing towards the partial negative atom, I would go w...
- Sat Nov 14, 2020 11:38 am
- Forum: Dipole Moments
- Topic: H-Bonds
- Replies: 14
- Views: 837
Re: H-Bonds
Hi!
Hydrogen bonds occur between atoms with lone pairs, but they also can only bond with Nitrogen, Oxygen and Fluorine
Hydrogen bonds occur between atoms with lone pairs, but they also can only bond with Nitrogen, Oxygen and Fluorine
- Wed Nov 11, 2020 11:56 pm
- Forum: Dipole Moments
- Topic: Polar covalent bonds
- Replies: 5
- Views: 245
Re: Polar covalent bonds
Hi!
The difference between the two is that a dipole-dipole attraction is the force between molecules, while the polar covalent is in between atoms.
The difference between the two is that a dipole-dipole attraction is the force between molecules, while the polar covalent is in between atoms.
- Wed Nov 11, 2020 11:53 pm
- Forum: Bond Lengths & Energies
- Topic: 2D #13
- Replies: 2
- Views: 217
Re: 2D #13
Hi! How I solved it was I drew out the Lewis structures for all of them and looked at the different bonds. For multiple bonds (double & triple bonds), they are going to be "shorter and stronger".So for example, in part a, CO has a triple bond, so it will be the strongest. I will attach...
- Sun Nov 08, 2020 11:37 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Identify these type if problems
- Replies: 4
- Views: 164
Re: Identify these type if problems
Hi!
Normally when the question is asking for the most stable structure, you are going to want to find the formal charge.
Normally when the question is asking for the most stable structure, you are going to want to find the formal charge.
- Fri Nov 06, 2020 11:33 pm
- Forum: Student Social/Study Group
- Topic: Making it through Midterm Results
- Replies: 13
- Views: 769
Re: Making it through Midterm Results
Hi!
One of the things that probably helped me the most was definitely attending as many UA sessions as possible. The worksheets are super helpful, but also a lot of people will ask questions that you didn't even think up but end up being super important. Textbook problems were very helpful as well!
One of the things that probably helped me the most was definitely attending as many UA sessions as possible. The worksheets are super helpful, but also a lot of people will ask questions that you didn't even think up but end up being super important. Textbook problems were very helpful as well!
- Fri Nov 06, 2020 1:58 am
- Forum: Formal Charge and Oxidation Numbers
- Topic: Shortcut for Formal Charge
- Replies: 19
- Views: 1680
Re: Shortcut for Formal Charge
Hi!
I would say the easiest way to remember it is # of valence electrons- # of lines & dots around that element
I would say the easiest way to remember it is # of valence electrons- # of lines & dots around that element
- Wed Nov 04, 2020 11:35 pm
- Forum: Ionic & Covalent Bonds
- Topic: Learning Outline 3
- Replies: 6
- Views: 376
Re: Learning Outline 3
Hi!
I would definitely recommend going to the UA sessions. They have really helpful worksheets and give very detailed and helpful explanations for everything!
I would definitely recommend going to the UA sessions. They have really helpful worksheets and give very detailed and helpful explanations for everything!
- Wed Nov 04, 2020 11:32 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Are there subshells past f?
- Replies: 28
- Views: 1191
Re: Are there subshells past f?
Hi!
Dr. Lavelle said there are subshells past f but the only ones we need to worry about for this class are s,p,d,f.
Dr. Lavelle said there are subshells past f but the only ones we need to worry about for this class are s,p,d,f.
- Tue Nov 03, 2020 12:23 am
- Forum: Trends in The Periodic Table
- Topic: # of electrons
- Replies: 23
- Views: 704
Re: # of electrons
Hi!
The total number of electrons is equal to the atomic number.
The total number of electrons is equal to the atomic number.
- Thu Oct 29, 2020 10:19 am
- Forum: DeBroglie Equation
- Topic: p
- Replies: 19
- Views: 898
Re: p
P represent momentum! The equation to find momentum is p=(mass)(velocity).Also remember to convert to SI units!
- Thu Oct 29, 2020 10:17 am
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: position units
- Replies: 19
- Views: 1411
Re: position units
Hi!
While you're solving the problem, you should always convert to meters since it is an SI unit. Sometimes the question will ask for the wavelength in other units like nm, but that should only be converted at the very end.
While you're solving the problem, you should always convert to meters since it is an SI unit. Sometimes the question will ask for the wavelength in other units like nm, but that should only be converted at the very end.
- Thu Oct 29, 2020 10:15 am
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Rydberg's
- Replies: 7
- Views: 328
Re: Rydberg's
Hi!
The Rydberg's equation only work for for Hydrogen atoms and other single electron atoms.
The Rydberg's equation only work for for Hydrogen atoms and other single electron atoms.
- Wed Oct 28, 2020 1:38 am
- Forum: Einstein Equation
- Topic: Work Function and Energy of Photons
- Replies: 4
- Views: 276
Re: Work Function and Energy of Photons
Hi!
If the kinetic energy is equal to 0, you would set hv equal to the work function. This is because in order to remove an electron from the surface, the energy of the photon must be at least equal to or greater to the work function.
If the kinetic energy is equal to 0, you would set hv equal to the work function. This is because in order to remove an electron from the surface, the energy of the photon must be at least equal to or greater to the work function.
- Tue Oct 27, 2020 1:12 am
- Forum: Administrative Questions and Class Announcements
- Topic: how far in the sapling hw does midterm 1 go to
- Replies: 5
- Views: 313
Re: how far in the sapling hw does midterm 1 go to
Hi!
Sapling randomized the homework questions so it's hard to tell which is which. Dr. Lavelle said we definitely need to know 19 of them, so I just picked out the 19 questions with topics that we have learned.
Sapling randomized the homework questions so it's hard to tell which is which. Dr. Lavelle said we definitely need to know 19 of them, so I just picked out the 19 questions with topics that we have learned.