Search found 27 matches
- Sat Mar 17, 2018 7:34 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Test 2 #5a
- Replies: 1
- Views: 308
Test 2 #5a
Can someone help me with Test 2 #5a?
- Sat Mar 17, 2018 7:32 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Test 2 #7
- Replies: 3
- Views: 416
Test 2 #7
Can someone help me out with Test 2 #7?
- Wed Mar 14, 2018 9:45 am
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: Reaction Diagrams
- Replies: 1
- Views: 411
Reaction Diagrams
For the Reaction Diagrams/Graphs that we draw for Kinetics and Thermo, are PE/E and G interchangeable for the y-axis?
- Sun Mar 11, 2018 10:52 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Cell Diagrams
- Replies: 6
- Views: 810
Cell Diagrams
In a cell diagram, how do you determine which atom/molecule goes first?
EX. Test Question #6C
EX. Test Question #6C
- Sun Mar 11, 2018 10:49 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3648193
Re: Post All Chemistry Jokes Here
Once I told a chemistry joke. There was no reaction ...
- Sun Mar 11, 2018 10:46 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Last Lecture
- Replies: 1
- Views: 259
Last Lecture
Will Monday be our last lecture (in terms of new information)?
- Sun Mar 04, 2018 11:00 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Kinetics Test
- Replies: 3
- Views: 493
Kinetics Test
From what I understand, Test #3 (15.1-15.6) will correspond to all the lectures on Kinetics and 1/2 of the lecture from Friday (March 2nd)--the part before Reaction Mechanisms. Can someone confirm this?
- Sun Mar 04, 2018 10:55 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Reaction Mechanisms
- Replies: 1
- Views: 268
Reaction Mechanisms
From the lecture I understand that the slowest step determines the rate of overall reaction (and that its Step 1) will it always be Step 1 or is there a way to determine the slowest step?
- Sun Mar 04, 2018 7:11 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3648193
Re: Post All Chemistry Jokes Here
I tell bad chemistry jokes because all the good ones argon.
- Sun Feb 25, 2018 8:15 pm
- Forum: Method of Initial Rates (To Determine n and k)
- Topic: Initial Rates
- Replies: 3
- Views: 465
Initial Rates
Would there ever been an instance where we have to determine n and k with non-initial rates or can we assume for all questions that it will be initial rates?
- Sun Feb 25, 2018 8:11 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: NERNST
- Replies: 4
- Views: 635
NERNST
Just to clarify--the value 0.0592 V can only be used at 25 degrees C and with log Q? Can it be used with ln as well?
- Sun Feb 25, 2018 8:08 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3648193
Re: Post All Chemistry Jokes Here
Q: Why does hamburger have lower energy than steak?
A: Because it's in the ground state.
A: Because it's in the ground state.
- Sun Feb 11, 2018 11:41 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: troutons rule
- Replies: 3
- Views: 573
Re: troutons rule
It is not listed in the lecture outlines, but it is pretty simple: the definition from the book is "the empirical observation that the entropy of vaporization at the boiling point is approximately 85 J/Kmol for many liquids." Self-Test 9.7A and B are some examples of how you can use the ru...
- Sun Feb 11, 2018 11:00 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Gold Example
- Replies: 1
- Views: 258
Gold Example
Did anyone write down the example that involved gold in last Friday's lecture? I missed some parts of the lecture in my notes.
- Sun Feb 11, 2018 10:50 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Gibbs Free Energy and Spontaneity
- Replies: 2
- Views: 504
Re: Gibbs Free Energy and Spontaneity
Yes I believe so.
- Sun Feb 04, 2018 10:39 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Exothermic and Spontaneous
- Replies: 4
- Views: 9923
Re: Exothermic and Spontaneous
An exothermic reaction is when a reaction has a net release of heat, system loses heat (ΔH is negative). Spontaneous means that the reaction happens without any added help (ie. any extra energy). Spontaneous reactions have a negative ΔG. So exothermic and endothermic reactions can be spontaneous dep...
- Sun Feb 04, 2018 9:35 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Midterm Question
- Replies: 3
- Views: 486
Midterm Question
Does anyone know which lecture will be the last lecture that will be on the midterm? Will it be Friday or Wednesday?
- Wed Jan 31, 2018 12:15 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Chem Community Posts
- Replies: 5
- Views: 880
Chem Community Posts
I apologize if this seems redundant but I am confused about the Chemistry Community post deadlines. I read on one board that it is due at 11:59pm on Sunday and overheard that it is due midnight on Sunday (aka 1 minute after 11:59pm on Saturday. Which time is correct? [is Saturday night the last time...
- Sun Jan 28, 2018 4:37 pm
- Forum: Calculating Work of Expansion
- Topic: Diagram of Reversible Expansion
- Replies: 3
- Views: 498
Diagram of Reversible Expansion
On the diagram of isothermal reversible expansion from lecture on Wednesday (1/24/18) it said that one side of the piston had an ideal gas, and one side was a vacuum. What exactly is a vacuum (and what does it entail/mean in the diagram)?
- Sun Jan 28, 2018 4:31 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Week 3 Friday Lecture
- Replies: 2
- Views: 356
Week 3 Friday Lecture
During the last couple minutes of the lecture, I missed the last sentence in my notes--Does anyone know what it said on the slide after "Magnitude of ΔS depends on T at which heat is transferred"? Thank you!
- Mon Jan 22, 2018 8:15 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Positional (Residua) Entropy
- Replies: 1
- Views: 281
Positional (Residua) Entropy
Can someone clarify what positional entropy is? And what is the difference between it and thermal entropy?
- Sun Jan 21, 2018 8:32 am
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: R Constant
- Replies: 2
- Views: 332
Re: R Constant
It depends on what values are given or what values you can find based on what is given= 0.08206 L*atm(K^-1)(mol^-1) versus 8.314 J(K^-1)(mol^-1). Notice that the units for each are different, so you use one if you are given (or can find) L and atm and the other if you are given (or can find) J.
- Sun Jan 21, 2018 1:35 am
- Forum: Calculating Work of Expansion
- Topic: Reversible vs Isothermal
- Replies: 3
- Views: 424
Re: Reversible vs Isothermal
I believe that a reversible expansion is when the change in pressure is infinitesimal so that the Pinternal~Pexternal and the V change is also infinitesimal. A isothermal expansion is an expansion with constant temperature.
- Wed Jan 17, 2018 11:30 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Units for Enthalpy [ENDORSED]
- Replies: 1
- Views: 329
Units for Enthalpy [ENDORSED]
I noticed on some of the answers in the solutions manual that reaction enthalpies were given in kJ and some were in kJ/mol. Can someone explain when you get which units? Does it depend on the method you use?
- Sun Jan 14, 2018 8:23 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: q equations
- Replies: 2
- Views: 503
q equations
Can someone explain the difference between q=nCmΔT versus q=10g CspΔT? Its from lecture 3 towards the end of lecture.
- Sun Jan 14, 2018 6:54 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Most Staple Phases
- Replies: 3
- Views: 282
Most Staple Phases
During lecture, did anyone write down all of the most stable phases of common elements? (I missed a few)
- Fri Jan 12, 2018 2:24 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Textbook Question
- Replies: 1
- Views: 246
Textbook Question
I took 14A with a different professor so I was wondering approximately which chapters in the chem textbook are covered in 14A (looking to refresh on chem concepts)?