Search found 30 matches
- Mon Mar 19, 2018 12:00 am
- Forum: Van't Hoff Equation
- Topic: Practice Test
- Replies: 5
- Views: 1088
Re: Practice Test
We will not have to
- Mon Mar 19, 2018 12:00 am
- Forum: Van't Hoff Equation
- Topic: Finding K
- Replies: 5
- Views: 1035
Re: Finding K
We do not need them
- Sun Mar 18, 2018 11:59 pm
- Forum: General Rate Laws
- Topic: Rate constant units
- Replies: 6
- Views: 1259
Re: Rate constant units
In general the constant is M^1-n*time^-1
- Sun Mar 11, 2018 11:54 pm
- Forum: Second Order Reactions
- Topic: the slope
- Replies: 12
- Views: 1604
- Sun Mar 11, 2018 11:50 pm
- Forum: Zero Order Reactions
- Topic: graph of 0 order
- Replies: 10
- Views: 2014
- Sun Mar 11, 2018 11:49 pm
- Forum: Zero Order Reactions
- Topic: Half-Life of Zero Order
- Replies: 3
- Views: 645
Re: Half-Life of Zero Order
It would probably be good to know for the test. Even though the book mentioned it won't be used Lavelle might decide to put it in a problem
- Sun Mar 04, 2018 11:56 pm
- Forum: General Rate Laws
- Topic: graphs
- Replies: 2
- Views: 388
- Sun Mar 04, 2018 11:52 pm
- Forum: General Rate Laws
- Topic: zero order in rate laws
- Replies: 8
- Views: 1072
Re: zero order in rate laws
No, the zero order reaction has no effect on the rate law so normally its not included.
- Sun Mar 04, 2018 11:50 pm
- Forum: General Rate Laws
- Topic: Negative Order 15.3
- Replies: 2
- Views: 386
Re: Negative Order 15.3
Also for a negative order reaction the overall order is normally undefined (like 2nd order + -1 order has a more complex rate constant than just first order)
- Sun Feb 25, 2018 11:50 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: Nernst Equation
- Replies: 6
- Views: 949
Re: Nernst Equation
It is the total amount of electrons transferred. This can be found by combining two half reactions for the redox reactions.
- Sun Feb 25, 2018 11:37 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: calculating n
- Replies: 9
- Views: 1211
Re: calculating n
To calculate n you would need to find the number of electrons transferred in each half reaction. If they match up, that is your n value. If they don't the lowest multiple of the two is you n value.
- Sun Feb 25, 2018 11:34 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: standard conditions [ENDORSED]
- Replies: 4
- Views: 613
Re: standard conditions [ENDORSED]
I believe standard conditions just represents things like 298K and 1atm. It doesn't necessarily mean the system is at equilibrium
- Sun Feb 18, 2018 11:49 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Nernst Equation (log vs. ln)
- Replies: 5
- Views: 6532
Re: Nernst Equation (log vs. ln)
During discussion my TA mentioned that there is no difference, but if you use ln it is easier to relate to other equations that also use ln
- Sun Feb 18, 2018 11:45 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: E vs E naught
- Replies: 3
- Views: 4279
E vs E naught
Can someone explain the difference between E and E naught? Is it the same as G vs G naught?
- Sun Feb 18, 2018 11:43 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Quiz 2
- Replies: 1
- Views: 346
Quiz 2
Should we expect the same format for Quiz 2 as Quiz 1? Some multiple choice and mostly free response?
- Fri Feb 09, 2018 11:21 am
- Forum: Administrative Questions and Class Announcements
- Topic: Lecture Slides
- Replies: 6
- Views: 927
Lecture Slides
I know that Lavelle has lecture outlines but does he post the actual slides anywhere?
- Fri Feb 09, 2018 10:48 am
- Forum: Administrative Questions and Class Announcements
- Topic: Bruin Cast
- Replies: 5
- Views: 876
Re: Bruin Cast
Its not but he does post lecture outlines like this:
https://lavelle.chem.ucla.edu/wp-conten ... rochem.pdf
to help when you are reading through the textbook
https://lavelle.chem.ucla.edu/wp-conten ... rochem.pdf
to help when you are reading through the textbook
- Fri Feb 09, 2018 10:36 am
- Forum: Administrative Questions and Class Announcements
- Topic: Midterm Review Sessions
- Replies: 1
- Views: 332
Midterm Review Sessions
Does anyone have a link for the midterm review sessions? I can't seem to find it on the website
- Fri Feb 02, 2018 3:20 am
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: G=H-TS
- Replies: 4
- Views: 818
Re: G=H-TS
As a general guideline for deltaG:
+deltaS and -deltaH means spontaneous at all temp
+deltaS and +deltaH means spontaneous at high temp
-deltaS and-deltaH means spontaneous at low temp
-deltaS and +deltaH means not spontaneous at all
+deltaS and -deltaH means spontaneous at all temp
+deltaS and +deltaH means spontaneous at high temp
-deltaS and-deltaH means spontaneous at low temp
-deltaS and +deltaH means not spontaneous at all
- Fri Feb 02, 2018 3:14 am
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: bond enthalpy [ENDORSED]
- Replies: 4
- Views: 581
Re: bond enthalpy [ENDORSED]
I think that bond enthalpies can be considered constants that aren't affected by outside sources like polarity
- Fri Feb 02, 2018 3:02 am
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Calculation methods
- Replies: 3
- Views: 480
Re: Calculation methods
Yes, I believe that you can use any of the methods we have previously learned to calculate delta H
- Fri Jan 26, 2018 11:02 am
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: deltaH Units
- Replies: 5
- Views: 566
Re: deltaH Units
I believe that standard delta H and delta H of a reaction are in KJ while delta H of formation is in KJ/mol
- Fri Jan 26, 2018 10:57 am
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: The sign of q
- Replies: 5
- Views: 1189
Re: The sign of q
I think the system should be thought of as the calorimeter which is gaining heat and thus the q is considered positive
- Fri Jan 26, 2018 10:42 am
- Forum: Phase Changes & Related Calculations
- Topic: Heat and Work relation
- Replies: 6
- Views: 734
Re: Heat and Work relation
Normally when solving delta U = q(heat) + w(work) q and w are calculated separately. The work could have a negative or positive value depending on the delta V in the equation.
- Fri Jan 19, 2018 9:19 am
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: 8.103
- Replies: 2
- Views: 255
Re: 8.103
Yes, in the average kinetic energy equation R represents the ideal gas constant: 8.3145 J/K*mol
- Fri Jan 19, 2018 9:17 am
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: 8.29
- Replies: 4
- Views: 276
8.29
In the solution manual it says that NO2 has a higher heat capacity because of "more possible bond vibrations." Is it safe to assume that a molecule with more bonds will have a higher heat capacity?
- Fri Jan 19, 2018 9:11 am
- Forum: Phase Changes & Related Calculations
- Topic: HW question
- Replies: 5
- Views: 529
Re: HW question
Yes, you can choose any 14 questions from chapter 8. As of right now we haven't learned any other chapters.
- Thu Jan 11, 2018 10:46 pm
- Forum: Phase Changes & Related Calculations
- Topic: Ideal Gas
- Replies: 5
- Views: 445
Re: Ideal Gas
As mentioned above an ideal gas is a hypothetical version of a gas whose molecules do not repel/attract eachother and also take up no volume. This allows you to apply equations like PV=nRT to solve problems. In the real world it is unlikely that any gases follow this law.
- Thu Jan 11, 2018 10:40 pm
- Forum: Phase Changes & Related Calculations
- Topic: Endo and Exothermic Ways to Remember
- Replies: 28
- Views: 11658
Re: Endo and Exothermic Ways to Remember
I personally remember it from the acronym MEXOBENDO where the M stands for making and the B stands breaking. This gives you Making(bonds) EXOthermic and Breaking ENDOthermic
- Thu Jan 11, 2018 10:35 pm
- Forum: Phase Changes & Related Calculations
- Topic: Superheating
- Replies: 6
- Views: 3361
Re: Superheating
Superheating, or boiling delay occurs when a liquid is heated past its boiling point without actually boiling. This normally only occurs in homogeneous substances.