Search found 45 matches
- Sun Mar 18, 2018 9:45 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: State Functions
- Replies: 4
- Views: 762
Re: State Functions
I believe those four are the answers.
- Sun Mar 18, 2018 9:37 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: catalysts
- Replies: 3
- Views: 836
Re: catalysts
a catalyst is present before a reaction takes place, as opposed to an intermediate that is present after the reaction takes place.
- Sun Mar 18, 2018 9:33 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Saying Thank You to Dr. Lavelle
- Replies: 490
- Views: 557286
Re: Saying Thank You to Dr. Lavelle
Dear Dr. Lavelle, Thank you so much of your dedication to teaching. I really came into this class without a strong chemistry background but I rarely felt like that out me at a disadvantage. These past two quarters have really made be appreciate chemistry and all of its real world applications. Thank...
- Sun Mar 18, 2018 9:26 pm
- Forum: *Alkanes and Substituted Alkanes (Staggered, Eclipsed, Gauche, Anti, Newman Projections)
- Topic: nucleophiles
- Replies: 3
- Views: 3939
Re: nucleophiles
"A nucleophile is a chemical species that donates an electron pair to an electrophile to form a chemical bond in relation to a reaction"
- Sun Mar 18, 2018 9:24 pm
- Forum: Third Law of Thermodynamics (For a Unique Ground State (W=1): S -> 0 as T -> 0) and Calculations Using Boltzmann Equation for Entropy
- Topic: w
- Replies: 2
- Views: 698
Re: w
yes this is correct
Re: draw
Can you expand? We did have to draw a lewis structure is thats what you're talking about.
- Sun Mar 11, 2018 11:07 pm
- Forum: Calculating Work of Expansion
- Topic: Midterm Q4A
- Replies: 3
- Views: 497
Re: Midterm Q4A
Because the external pressure was constant the process was irreversible, and that equation is for reversible processes.
- Sun Mar 11, 2018 11:03 pm
- Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
- Topic: Molar Entropy
- Replies: 9
- Views: 1280
Re: Molar Entropy
Jacquelyn Hill 1 wrote:Also, is the size a more significant factor in determining this than the state that the molecule is in?
I have this same question.
- Sun Mar 11, 2018 11:01 pm
- Forum: *Free Energy of Activation vs Activation Energy
- Topic: Relation between k and activation energy
- Replies: 10
- Views: 5626
Relation between k and activation energy
What exactly is the relationship between k and activation energy?
- Wed Mar 07, 2018 2:33 pm
- Forum: Method of Initial Rates (To Determine n and k)
- Topic: Unique rates
- Replies: 4
- Views: 683
Re: Unique rates
Yes this could potentially and most likely will be on the test.
- Sun Feb 25, 2018 10:00 pm
- Forum: Interesting Applications: Rechargeable Batteries (Cell Phones, Notebooks, Cars), Fuel Cells (Space Shuttle), Photovoltaic Cells (Solar Panels), Electrolysis, Rust
- Topic: Electrolyis
- Replies: 3
- Views: 607
Re: Electrolyis
Just conceptual knowledge, not calculations.
- Sun Feb 25, 2018 9:16 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: Units
- Replies: 7
- Views: 1201
Re: Units
Bryan Vega 2E wrote:Unless the question specifically asks you to state your answer in a particular unit, it does not matter what units you choose to use.
So essentially you choose?
- Sun Feb 25, 2018 9:13 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: Chapter 15 related videos
- Replies: 6
- Views: 882
Re: Chapter 15 related videos
Julianna Thrasher 1B wrote:I like Crash Course by John Green! Very basic review just to remind you of topics in the chapter. https://www.youtube.com/watch?v=7qOFtL3VEBc
I found this video to be a helpful overview!
- Sun Feb 18, 2018 10:25 pm
- Forum: Balancing Redox Reactions
- Topic: Test #2
- Replies: 5
- Views: 688
Re: Test #2
And all lecture material up to last Friday
- Sun Feb 18, 2018 10:20 pm
- Forum: Balancing Redox Reactions
- Topic: Half-Reactions on Test 2
- Replies: 5
- Views: 738
Re: Half-Reactions on Test 2
Mishta Stanislaus 1H wrote:In a UA session we were told that he would provide a long list of half reactions and we would just have to choose from the list which are useful per problem.
With the standard reduction potentials given as well
- Sun Feb 18, 2018 10:19 pm
- Forum: Balancing Redox Reactions
- Topic: Half-Reactions on Test 2
- Replies: 5
- Views: 738
Re: Half-Reactions on Test 2
In a UA session we were told that he would provide a long list of half reactions and we would just have to choose from the list which are useful per problem.
- Sun Feb 18, 2018 10:16 pm
- Forum: Balancing Redox Reactions
- Topic: Test 2
- Replies: 5
- Views: 663
Re: Test 2
I was told by a UA that he provides a long list of half reactions and we just have to find with ones we need for the specific problem from the list
- Sun Feb 11, 2018 11:42 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Test #7
- Replies: 7
- Views: 904
Re: Test #7
The correct answer given during the review session was 16 degrees Celsius.
- Sun Feb 11, 2018 11:39 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Revsersible vs. Irreversible reactions
- Replies: 3
- Views: 515
Re: Revsersible vs. Irreversible reactions
The equations also differ
reversible work, W=-nRTln(v2/v1)
irreversible work, W= -Pext (v2-v1)
reversible work, W=-nRTln(v2/v1)
irreversible work, W= -Pext (v2-v1)
- Sun Feb 11, 2018 11:31 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Cp v. Cv!
- Replies: 5
- Views: 828
Re: Cp v. Cv!
Hi! I've been struggling with the same question but in the review session we were told that unless the problem specifically says that pressure is constant we use Cv.
- Mon Feb 05, 2018 7:37 am
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Gibbs Free Energy Equations
- Replies: 3
- Views: 602
Re: Gibbs Free Energy Equations
In friday's lecture (and other prior unrelated lectures), Dr. Lavelle set two gibbs free energy equations equal to each other. Can we assume that we can set any of these equations for gibbs free energy equal to each other? (not standard gibbs free energy because that's not the same as just gibbs fr...
- Mon Feb 05, 2018 7:34 am
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Equations
- Replies: 4
- Views: 521
Re: Equations
I don’t think this will be required for us to know
- Mon Feb 05, 2018 7:33 am
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Delta G equal Zero [ENDORSED]
- Replies: 4
- Views: 709
Delta G equal Zero [ENDORSED]
Des delta G and delta S have to equal zero for a reaction to be reversible? Can someone explain the reason?
- Sun Jan 28, 2018 4:30 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: degeneracy
- Replies: 3
- Views: 462
Re: degeneracy
This discussion helped me understand degeneracy a lot better,
viewtopic.php?t=9912
viewtopic.php?t=9912
- Sun Jan 28, 2018 4:26 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Entropy vs. Degeneracy [ENDORSED]
- Replies: 5
- Views: 668
Re: Entropy vs. Degeneracy [ENDORSED]
This discussion helped be understand the distinction much better, hope it helps!
viewtopic.php?t=9912
viewtopic.php?t=9912
- Tue Jan 23, 2018 12:18 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Week 3 Test Topic is endorsed
- Replies: 37
- Views: 4891
Re: Week 3 Test Topic is endorsed
Natalie LeRaybaud 1G wrote:After going through the homework I noticed numbers 3-13,25-31, and 47-49 all have to do with calculating work or internal energy. I would suggest studying all the other homework problems specifically for this upcoming test.
Can anyone else confirm that these problems aren't going to be tested on?
- Sun Jan 21, 2018 8:51 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Week 3 Test Topic is endorsed
- Replies: 37
- Views: 4891
Re: Week 3 Test Topic is endorsed
Miranda 1J wrote:For the test do we need to know how to derive the work equation? I know Dr. Lavelle said work and DU won't be on the test but this seems like a conceptual thing to me so I'm not entirely sure.
I have this same question
- Sun Jan 21, 2018 8:47 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Specific enthalpy
- Replies: 1
- Views: 244
Specific enthalpy
Do we need to know about the specific enthalpy?
- Sun Jan 21, 2018 8:46 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Problem 8.99
- Replies: 6
- Views: 645
Re: Problem 8.99
On the test will the enthalpy of formation values be provided in the problem or do we have to memorize?
- Sun Jan 14, 2018 5:51 pm
- Forum: Phase Changes & Related Calculations
- Topic: Endo and Exothermic Ways to Remember
- Replies: 28
- Views: 11643
Re: Endo and Exothermic Ways to Remember
I usually think about the prefixes. The "en" in endothermic sounds like in and the "ex" in exothermic reminds me of exit.
- Sun Jan 14, 2018 4:26 pm
- Forum: Phase Changes & Related Calculations
- Topic: Constant temperature
- Replies: 3
- Views: 284
Constant temperature
During a phase change, say from solid to liquid, why does the temperature remain constant and not increase?
- Sat Dec 09, 2017 5:11 pm
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: 12.23 [ENDORSED]
- Replies: 7
- Views: 1250
Re: 12.23 [ENDORSED]
elliekauffman1I wrote:Why is Kw=x^2? Doesn't that imply that H3O and OH are the same value? And if so, then how are we supposed to know that?
I also need help with this question
- Tue Dec 05, 2017 10:15 pm
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: 12.67
- Replies: 1
- Views: 409
12.67
Rank the following solutions in order of increasing pH: (a) 1.0 10 5 m HCl(aq); (b) 0.20 m CH3NH3Cl(aq); (c) 0.20 m CH3COOH(aq); (d) 0.20 m C6H5NH2(aq). Justify your ranking. For this problem would be expected to know the answer without a specific K or Kb value, because the solution manual doesn’t u...
- Sun Nov 26, 2017 10:05 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Aqueous and Gaseous Phases
- Replies: 3
- Views: 382
Re: Aqueous and Gaseous Phases
Could someone please expand on this answer?
- Sun Nov 26, 2017 10:01 pm
- Forum: Ideal Gases
- Topic: Reading the textbook
- Replies: 262
- Views: 150860
Re: Reading the textbook
I️ think the best way to approach the textbook is by using the lecture notes as a sort of outline for the book. That way you can focus on the relevant informations as delivered in class. This method weeds out some of the overly complex detail in the textbook. Hope that helps!
- Mon Nov 13, 2017 12:18 am
- Forum: Octet Exceptions
- Topic: Radical [ENDORSED]
- Replies: 2
- Views: 565
Radical [ENDORSED]
What is the best way to determine where the radical will be placed?
- Mon Nov 13, 2017 12:15 am
- Forum: Bond Lengths & Energies
- Topic: Bond Length
- Replies: 8
- Views: 3383
Re: Bond Length
We can determine the bond length by seeing how many electrons are being shared. The higher the bond order, the stronger the pull between the atoms and the shorter the length of the bond. Hope that helps!
- Sun Oct 29, 2017 10:19 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Trouble on a question I seen on the internet relating to this topic we learned in class!
- Replies: 3
- Views: 559
Re: Trouble on a question I seen on the internet relating to this topic we learned in class!
Hello, just to clear up any confusion I believe the answer above is the correct one, Zinc, as opposed to the previous answer because the 3d orbital is listed first but the 4s must be filled first.
- Sun Oct 29, 2017 10:14 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: P-Orbital
- Replies: 5
- Views: 754
Re: P-Orbital
Just a reiteration, but yes you could switch those variables. They serve the purpose of showing the orbital is three dimensional.
- Sun Oct 22, 2017 10:43 pm
- Forum: *Shrodinger Equation
- Topic: HΨ=EΨ [ENDORSED]
- Replies: 5
- Views: 4488
Re: HΨ=EΨ [ENDORSED]
The purpose was to be able to find the m,l,etc, values I believe .
- Sun Oct 22, 2017 10:41 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Px, Py, Pz
- Replies: 10
- Views: 1316
Re: Px, Py, Pz
I'm curious about this as well, will we be penalized for doing it a different way as him?
- Sun Oct 15, 2017 10:35 pm
- Forum: Properties of Electrons
- Topic: Atomic Spectra [ENDORSED]
- Replies: 3
- Views: 535
Re: Atomic Spectra [ENDORSED]
I understand the second half of the explanation, just not the first concerning the division of one by the number of wavelengths.
- Sun Oct 15, 2017 2:03 pm
- Forum: Photoelectric Effect
- Topic: Post Assessment #28 [ENDORSED]
- Replies: 4
- Views: 644
Re: Post Assessment #28 [ENDORSED]
To answer this question you must convert the given work function from kJ to J. Then you must divide by avagadro's number to find the energy required per atom as opposed to per mole.
- Mon Oct 09, 2017 10:44 pm
- Forum: Properties of Light
- Topic: Amplitude
- Replies: 6
- Views: 934
Amplitude
I understand that wave length and frequency have and inverse relationship due to the given equation, but does amplitude relate to these in any way?
- Mon Oct 09, 2017 10:36 pm
- Forum: Properties of Light
- Topic: Chapter 1 Problem 7b
- Replies: 3
- Views: 330
Re: Chapter 1 Problem 7b
I had the same question, thanks for clarifying!