Search found 60 matches
- Sun Mar 17, 2019 10:39 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Effect of increased concentration on equilibrium
- Replies: 9
- Views: 1432
Re: Effect of increased concentration on equilibrium
What about if the reaction is not at equilibrium? How increasing the concentration affect the equilibrium?
- Sun Mar 17, 2019 10:37 am
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Arrhenius eq
- Replies: 3
- Views: 661
Re: Arrhenius eq
Yes, as others have stated, we can assume that A=1 unless it is otherwise stated in the problem.
- Sun Mar 17, 2019 10:35 am
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: pKa and pKb
- Replies: 4
- Views: 705
Re: pKa and pKb
when given pKa and asked for ph, solve for Ka with pKa= -logKa which would mean 10^(-pKa)= Ka Then, if the reaction is acidic, find the Ka equilibrium equation for the reaction Usually, an initial Molarity will be given for the Reactant Once the Ka equation is written, set it equal to the Ka value ...
- Fri Mar 15, 2019 10:16 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Equation sheet
- Replies: 4
- Views: 474
Re: Equation sheet
For what type of questions would we apply the Nernst Equation?
- Sat Mar 09, 2019 8:31 pm
- Forum: General Rate Laws
- Topic: Overall sum
- Replies: 7
- Views: 757
Re: Overall sum
Can someone explain why we add m and n?
- Sat Mar 09, 2019 8:30 pm
- Forum: Student Social/Study Group
- Topic: Final
- Replies: 24
- Views: 2120
Re: Final
How do you guys study for the final? I still haven't found a study method that works for me and I'm really trying to do my best for this final!
- Sat Mar 09, 2019 8:29 pm
- Forum: First Order Reactions
- Topic: Pseudo Rate Laws
- Replies: 1
- Views: 216
Re: Pseudo Rate Laws
The first order claims that If the concentration of a reactant remains constant, its concentration can be included in the rate constant. However, i am not too sure about the second order. If someone can clarify that order I would appreciate it.
- Sat Mar 09, 2019 8:18 pm
- Forum: General Rate Laws
- Topic: Rate Laws
- Replies: 8
- Views: 670
Re: Rate Laws
I'm still confused on why we apply rate laws to certain questions. Can someone explain what a rate law is and why it is useful?
- Sun Mar 03, 2019 8:19 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Q and K with the Nernst Equation
- Replies: 3
- Views: 430
Re: Q and K with the Nernst Equation
You would have to know the values of both, but usually K is given and you solve for Q.
- Sun Mar 03, 2019 8:18 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Cell Diagram
- Replies: 4
- Views: 400
Re: Cell Diagram
I'm not too sure but I believe H+ is included in a cell diagram, but I know for sure H20(l) is not included.
- Sun Mar 03, 2019 8:16 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: Cell diagram
- Replies: 4
- Views: 460
Re: Cell diagram
As a follow up to your question, when and why do we add Pt(s) to the ends of a cell diagram?
- Sun Mar 03, 2019 8:15 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: Melting of ice
- Replies: 9
- Views: 1010
Re: Melting of ice
As mentioned above, Delta G would be less than zero because the reaction is spontaneous.
- Sun Feb 24, 2019 8:38 am
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: q=mCdeltaT
- Replies: 15
- Views: 8103
Re: q=mCdeltaT
What would be the final units for the equations? In other words, if we used moles, what would our final units be, and if we used m, what would our final units be? I get confused with the two.
- Sun Feb 24, 2019 8:36 am
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: Test 3
- Replies: 14
- Views: 2277
Re: Test 3
Up to what section of electrochemistry do we need to study? I'm still a little confused so if someone can clarify that would be greatly appreciated.
- Sun Feb 24, 2019 8:34 am
- Forum: Balancing Redox Reactions
- Topic: Test 2 Material
- Replies: 13
- Views: 1298
Re: Test 2 Material
According to Lavelle, the test will cover everything up to Friday's lecture.
- Sun Feb 17, 2019 9:41 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: spontaneity
- Replies: 3
- Views: 341
Re: spontaneity
Spontaneity just means that a chemical process can happen without a major outside force acting on the chemical reaction. There are two outside forces, I believe they are enthalpy and entropy. If there are no major outside forces, as you say, then the only forces acting/producing the spontaneous rea...
- Sun Feb 17, 2019 9:38 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: delta G
- Replies: 3
- Views: 398
Re: delta G
A pretty simple explanation of what delta G indicates is the change in free energy of the system. In an exergonic reaction free energy is released, hence delta g is negative. In an endergonic reaction, free energy is inputed into the system, and delta g is positive.
- Sun Feb 17, 2019 9:33 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Nonexpansion Work
- Replies: 2
- Views: 359
Re: Nonexpansion Work
As you said, Gibbs Free Energy is the maximum amount of non-expansion work that can occur in a closed system.non-expansion work is work not involving pressure and volume, as the person above stated: electrical work.
- Tue Feb 12, 2019 3:11 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Lyndon's HOTDOG MIDTERM REVIEW SESSION!! FINALLY!
- Replies: 49
- Views: 11459
Re: Lyndon's HOTDOG MIDTERM REVIEW SESSION!! FINALLY!
Can someone please explain why 3E is false?
- Thu Feb 07, 2019 6:13 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Midterm
- Replies: 8
- Views: 866
Re: Midterm
will all of outline 4 be on the midterm? (including Gibbs Free Energy and the little part of Chapter 11 that is listed on the 6th edition outline) Or are will it be only up to section 9.11 in the sixth edition? I saw someone on another forum post that gibbs free energy will not be on the test, but ...
- Thu Feb 07, 2019 6:09 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Study Guides
- Replies: 15
- Views: 1190
Re: Study Guides
ariana_apopei1K wrote:Lyndon is probably going to make one that he'll go over in his review session this monday
Do you know where and what time his review session will be?
- Thu Feb 07, 2019 6:09 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Study Guides
- Replies: 15
- Views: 1190
Re: Study Guides
805132275 wrote:Are there any study guide/review sheets the TAs have made available for the midterm?
I know Joyce had a review session and she provided a worksheet that was very helpful. She said she was going to post it online, I just can't seem to find it.
- Sun Feb 03, 2019 8:21 pm
- Forum: Calculating Work of Expansion
- Topic: Units for pressure
- Replies: 10
- Views: 723
Re: Units for pressure
SydBenedict2H wrote:If its ever in bar, thats more or less equivalent to atm.
Exactly, I remember the professor saying the difference between bar and atm is very small.
- Sun Feb 03, 2019 8:20 pm
- Forum: Calculating Work of Expansion
- Topic: work done by vs on a system
- Replies: 5
- Views: 731
Re: work done by vs on a system
Katelyn Pham 4E wrote:This is correct. If work is done BY a system, energy is being released making it exothermic resulting in w being negative. If work is done ON a system, w is positive, because it is endothermic and energy is being put into the system.
Thank you for this summarization. It was very helpful.
- Sun Feb 03, 2019 8:18 pm
- Forum: Calculating Work of Expansion
- Topic: Equations for w
- Replies: 5
- Views: 451
Re: Equations for w
SydBenedict2H wrote:So does this mean we aren't going to have to use the integral formula to calculate anything on tests?
Most likely not, but I would still know it just in case.
- Sun Feb 03, 2019 8:17 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Recognizing delta u
- Replies: 2
- Views: 261
Re: Recognizing delta u
SydBenedict2H wrote:If they mention internal energy then they are referring to delta U and you should use its associated equations.
Is there a specific reason as to why we use the associated equations?
- Sat Jan 19, 2019 10:35 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Solving weak acid/base dissociations
- Replies: 4
- Views: 289
Re: Solving weak acid/base dissociations
Why is using the quadratic equation the only way to solve for a change in concentration?
- Sat Jan 19, 2019 10:24 am
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Understanding Q
- Replies: 9
- Views: 722
Re: Understanding Q
Can someone clarify what the significance of Q<K is and vice-versa?
- Sat Jan 19, 2019 10:22 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Test 1
- Replies: 6
- Views: 540
Re: Test 1
Was Wednesday's lecture the last new material we learned for the test?
- Sat Jan 12, 2019 12:19 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Solids and Liquids in Rxn
- Replies: 6
- Views: 581
Re: Solids and Liquids in Rxn
In response to the responses above me, why would solids and liquids not apply to the equilibrium constant?
- Sat Jan 12, 2019 12:18 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Equilibrium constants
- Replies: 2
- Views: 235
Re: Equilibrium constants
Personally, I believe equilibrium constants are important because they tell us how reversible a reaction is. For instance, if K>1, the reaction favors products. If K=1, there is an equal amount of products and reactants. If k<1, reactants are favored.
- Sat Jan 12, 2019 12:13 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: compression vs pressure
- Replies: 6
- Views: 646
Re: compression vs pressure
To the comment above me, you said the inverse relationship between volume and pressure only applies to gases. How would it apply to liquids, solids or aqueous solutions?
- Fri Dec 07, 2018 2:00 pm
- Forum: Administrative Questions and Class Announcements
- Topic: FINAL PRACTICE - Lyndon's Churro Review Session [ENDORSED]
- Replies: 118
- Views: 20821
Re: FINAL PRACTICE - Lyndon's Churro Review Session [ENDORSED]
Thank you for this! The one for the midterm really helped out and I hope this one does too. What will be the final topic covered during the review session?
- Sun Dec 02, 2018 6:48 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Polydentates
- Replies: 1
- Views: 137
Re: Polydentates
Water is always monodendate because it can only form one dative bond with a metal ion due to the oxygen molecule, which is why it is not bidentate
- Sun Dec 02, 2018 6:44 pm
- Forum: Naming
- Topic: Metal Prefixes
- Replies: 2
- Views: 284
Re: Metal Prefixes
I feel like that would revolve around memorization, and usually Lavelle stresses the idea of understanding the concepts as opposed to memorization so I doubt it. But hey, you never know. I may be wrong.
- Sun Dec 02, 2018 6:42 pm
- Forum: Amphoteric Compounds
- Topic: Examples
- Replies: 6
- Views: 584
Re: Examples
I believe Ammonia is one and also bicarbonate
- Sun Nov 25, 2018 5:05 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Xenon Tetrafluoride
- Replies: 3
- Views: 365
Re: Xenon Tetrafluoride
I've been asking myself the same thing. If someone can please clarify I would greatly appreciate it.
- Sun Nov 25, 2018 5:01 pm
- Forum: Hybridization
- Topic: Hybridization
- Replies: 5
- Views: 523
Re: Hybridization
I hope we only have to know sp3d2 but i'm not too sure if we have to know any other levels.
- Sun Nov 25, 2018 4:58 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Test 3
- Replies: 6
- Views: 556
Re: Test 3
Does anyone know the specific topics that will be on the test?
- Sun Nov 18, 2018 11:08 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: lone pair influence on shape
- Replies: 12
- Views: 4211
Re: lone pair influence on shape
Can someone explain the difference between bent and linear?
- Sun Nov 18, 2018 5:00 pm
- Forum: Resonance Structures
- Topic: Polar
- Replies: 8
- Views: 930
Re: Polar
Can someone explain how we identify if a bond is polar or non-polar?
- Sun Nov 18, 2018 4:38 pm
- Forum: Resonance Structures
- Topic: Resonance structures
- Replies: 7
- Views: 843
Re: Resonance structures
On a test would be asked to draw the resonance or hybrid structure?
- Sun Nov 11, 2018 8:31 pm
- Forum: Lewis Structures
- Topic: Lewis Structure
- Replies: 10
- Views: 800
Re: Lewis Structure
For the problems revolving lewis dot structures such as the one from the midterm, where you have to identify which element it is from the given structure, can someone explain how to find it? I was confused on that question.
- Sun Nov 11, 2018 8:27 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Midterm [ENDORSED]
- Replies: 14
- Views: 1496
Re: Midterm [ENDORSED]
Does anyone know when our next test is? I remember someone telling me it would be this upcoming Friday but that seems so soon. If someone knows please let me know, thanks in advance.
- Sun Nov 11, 2018 6:29 pm
- Forum: Electronegativity
- Topic: Electronegativity and Noble Gases
- Replies: 3
- Views: 174
Re: Electronegativity and Noble Gases
I'm not too sure but I believe that since the noble gases already have eight electrons, they don't wan't to attract any more electrons. Therefore because electronegativity measures the attraction between an atom and an electron, noble gases do not have electronegativity.
- Sun Nov 04, 2018 10:58 am
- Forum: Electronegativity
- Topic: What are the trends useful for?
- Replies: 12
- Views: 911
Re: What are the trends useful for?
Can someone explain why we use [Ar]
- Sun Nov 04, 2018 10:52 am
- Forum: General Science Questions
- Topic: Test 1 and Two Answer Key?
- Replies: 1
- Views: 256
Test 1 and Two Answer Key?
Does anyone have the answer key or know if there even is an answer key for test one and two? I got some questions wrong and i want to see how they are properly done
- Sun Nov 04, 2018 10:06 am
- Forum: Administrative Questions and Class Announcements
- Topic: MIDTERM PRACTICE - Garlic Bread Review Session [ENDORSED]
- Replies: 121
- Views: 17183
Re: MIDTERM PRACTICE - Garlic Bread Review Session [ENDORSED]
The review session on Saturday that went over this practice midterm really helped prepare me for the exam, thank you.
- Sun Oct 28, 2018 9:40 pm
- Forum: *Shrodinger Equation
- Topic: Application of Equation on test
- Replies: 5
- Views: 814
Re: Application of Equation on test
I was also worried about this prior to the exam but thankfully we did not have to use it on the exam
- Sun Oct 28, 2018 9:35 pm
- Forum: General Science Questions
- Topic: Khan Academy
- Replies: 10
- Views: 1486
Re: Khan Academy
I also continue to get emails from a website called "OneClass" that tends to have study guides for previous midterms etc. I'm wondering if anyone has actually used the website. But on another note, Khan Academy really helped me as an extra source to study for test 2.
- Sun Oct 28, 2018 9:32 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: 4s becomes higher energy
- Replies: 3
- Views: 2965
Re: 4s becomes higher energy
I also had a similar question regarding this, if someone can please answer I would greatly appreciate you.
- Sun Oct 21, 2018 10:05 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Step Up Session Worksheet (Monday + Friday, Hannah) [ENDORSED]
- Replies: 37
- Views: 3135
Re: Step Up Session Worksheet (Monday + Friday, Hannah) [ENDORSED]
Chem_Mod wrote:Here is the answer key for Week 2 Topics Step Up Worksheet!
Honestly, thank you so much for these. I feel like this is really good review for me as I tend to learn more from seeing how a problem is actually done. I look forward to attending one of your step up sessions.
- Sun Oct 21, 2018 10:00 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Advice from a Medical Student [ENDORSED]
- Replies: 297
- Views: 382835
Re: Advice from a Medical Student [ENDORSED]
Although this is over a year old, I really appreciate seeing posts like this. You're right, this class can be overwhelming and it's barely about to be week 4. Although you may never see this, thank you for posting this. I needed this inspiration for the upcoming test.
- Sun Oct 21, 2018 9:55 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Test On Tuesday
- Replies: 10
- Views: 1016
Re: Test On Tuesday
I wouldn't doubt it since it's in the outline. However, if there were to be a question regarding that section it shouldn't be too hard (I hope).
- Sun Oct 14, 2018 6:35 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Step Up Session Worksheet (Monday + Friday, Hannah) [ENDORSED]
- Replies: 37
- Views: 3135
Re: Step Up Session Worksheet (Monday + Friday, Hannah) [ENDORSED]
Will your sessions be every Friday and Monday for the rest of the quarter? Or just for this week?
- Sun Oct 14, 2018 6:31 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3004423
Re: Post All Chemistry Jokes Here
Q: Do you know any organic chemistry jokes?
A: I know Alkynes
A: I know Alkynes
- Sat Oct 13, 2018 6:13 pm
- Forum: DeBroglie Equation
- Topic: DeBroglie Equation
- Replies: 5
- Views: 500
Re: DeBroglie Equation
To the reply above this, why don't larger objects have a wave-like properties that can be measured?
- Sun Oct 07, 2018 2:21 pm
- Forum: Administrative Questions and Class Announcements
- Topic: DOWNLOAD SESSION WORKSHEETS HERE - Sundays 4-6pm (Karen) [ENDORSED]
- Replies: 135
- Views: 38444
Re: DOWNLOAD SESSION WORKSHEETS HERE - Sundays 4-6pm (Karen) [ENDORSED]
Are your workshops on Sundays and Sundays only?
- Sun Oct 07, 2018 11:42 am
- Forum: Significant Figures
- Topic: Rounding Using Significant Figures
- Replies: 10
- Views: 1439
Re: Rounding Using Significant Figures
Thanks for that explanation Tim. I was also confused on how to round using sig figs but I feel like your explanation actually helped. I'm just curious if we will lose points on tests/exams if we round to the incorrect decimal point.
- Sun Oct 07, 2018 11:37 am
- Forum: SI Units, Unit Conversions
- Topic: mol vs. mmol
- Replies: 12
- Views: 2644
Re: mol vs. mmol
In an exam would we ever have to convert from mol to mmol or vice-versa?