Search found 58 matches
- Sun Mar 15, 2020 2:57 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Athena
- Replies: 34
- Views: 3015
Re: Athena
Thank u Athena and Dr. DJ LAVELLE for the best in the business post-lecture songs
- Mon Mar 09, 2020 12:01 am
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: n in NFE
- Replies: 64
- Views: 2687
Re: n in NFE
the moles of electrons transferred
- Mon Mar 09, 2020 12:00 am
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Nernst
- Replies: 10
- Views: 582
Re: Nernst
Brandon Tao 1K wrote:What is nernst equation?
the equation developed by Nernst E=E with the little degree circle - RT/nF nlQ
- Sun Mar 08, 2020 11:59 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Nernst
- Replies: 10
- Views: 582
Re: Nernst
I used the log form for like literally everything.
- Sun Mar 08, 2020 11:58 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: linear plots
- Replies: 7
- Views: 523
Re: linear plots
know the axis and the orientation of the plot
- Sun Mar 08, 2020 11:56 pm
- Forum: General Rate Laws
- Topic: Elementary reactions
- Replies: 5
- Views: 289
Re: Elementary reactions
elementary as in simple, noncomplex, easy problems so to speak
- Sun Mar 08, 2020 11:55 pm
- Forum: Balancing Redox Reactions
- Topic: Reversing the anode
- Replies: 10
- Views: 647
Re: Reversing the anode
to get the real cell potential, we need to reverse the anode reduction reaction to make it an oxidation reaction.
- Sun Mar 01, 2020 11:25 pm
- Forum: General Rate Laws
- Topic: Preferred way to write reaction rate
- Replies: 5
- Views: 365
Re: Preferred way to write reaction rate
I mean, you can always just multiply the entire equation by a coefficient to get rid of the 1/2
- Sun Mar 01, 2020 11:21 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Direction of flow
- Replies: 5
- Views: 424
Re: Direction of flow
in a galvanic cell, the electrons flow in the spontaneous direction, and this flow of electrons is how the battery works, and is generally the only direction of flow, (anode to cathode), the salt bridge allows for ionization and keeps the solutions neutral.
- Sun Mar 01, 2020 11:17 pm
- Forum: Administrative Questions and Class Announcements
- Topic: what to know for test 2
- Replies: 10
- Views: 569
Re: what to know for test 2
electrochemistry
- Sun Mar 01, 2020 11:16 pm
- Forum: Balancing Redox Reactions
- Topic: 6K.3d
- Replies: 5
- Views: 354
Re: 6K.3d
[Cl][/2] is both reduced and oxidized, since the oxidized form is given, we need to find the reduced form.
- Sun Mar 01, 2020 11:06 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Anode and Cathode
- Replies: 8
- Views: 526
Re: Anode and Cathode
the electrons flow from the oxidation half reaction in the anode and flow into the reduction half reaction of the cathode (an ox, red cat)
- Sun Feb 23, 2020 5:49 pm
- Forum: Student Social/Study Group
- Topic: Final Jitters
- Replies: 457
- Views: 329257
Re: Final Jitters
a ridiculous amount of practice problems.
- Sun Feb 23, 2020 5:48 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: 5G.15
- Replies: 5
- Views: 311
Re: 5G.15
the answer key is wrong for sure
- Sun Feb 23, 2020 5:40 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Le Chatelier’s Principle
- Replies: 11
- Views: 638
Re: Le Chatelier’s Principle
increasing concentrations of products and reactants will cause the reaction to shift the same according to le chateliers principle.
- Sun Feb 23, 2020 5:38 pm
- Forum: Balancing Redox Reactions
- Topic: Balancing redox reactions
- Replies: 5
- Views: 403
Re: Balancing redox reactions
John Liang 2I wrote:The main principle is focus on charge first when balancing the redox rxn. When the number of electrons are balanced on both sides, the elements are probably going to be balanced. this is faster than looking at the elements first. hope this helps!
does this apply under any conditions?
- Fri Feb 21, 2020 9:56 pm
- Forum: General Science Questions
- Topic: THE RETURN OF DJ LAVELLE [ENDORSED]
- Replies: 6
- Views: 393
Re: THE RETURN OF DJ LAVELLE [ENDORSED]
Samuel G Rivera - Discussion 4I wrote:I'm in the 3pm lecture, but if it's the same song he played for us it's called Hazey by Glass Animals
ur a savior, thank you.
- Fri Feb 21, 2020 2:01 pm
- Forum: General Science Questions
- Topic: THE RETURN OF DJ LAVELLE [ENDORSED]
- Replies: 6
- Views: 393
THE RETURN OF DJ LAVELLE [ENDORSED]
DOES ANYONE KNOW THE NAME OF THE SONG DR. DJ LAVELLE WAS BOPPIN' TODAY AFTER CLASS? (FRIDAY 2/21/20 1PM LECTURE) THANKS.
- Sun Feb 09, 2020 2:57 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Nonlinear vs linear molecules
- Replies: 4
- Views: 874
Re: Nonlinear vs linear molecules
net rotational degrees of freedom, linear molecules only have 2, nonlinear molecules have 3 and the degrees of freedom contribute to the heat capacity.
- Sun Feb 09, 2020 2:56 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: What the calorimeter allows you to calculate according to conditions
- Replies: 5
- Views: 418
Re: What the calorimeter allows you to calculate according to conditions
at constant volume, deltaV = 0, so there is no w expansion work being done, which means deltaU is only equal to q (deltaU=q+w). At constant pressure, expansion work may be occurring, and this change can only be deltaH or q as a result of the heat given off.
- Sun Feb 09, 2020 2:50 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Review Sheet
- Replies: 3
- Views: 226
Re: Review Sheet
q=mC(deltaT) plug n chug
- Sun Feb 09, 2020 2:46 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: combustion rxn
- Replies: 2
- Views: 161
combustion rxn
What was the equation that Lavelle shared for calculating the change in mols for a combustion rxn?
- Sun Feb 09, 2020 2:44 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Topics on the Midterm
- Replies: 22
- Views: 994
Re: Topics on the Midterm
Basically everything up to outline 4, excluding the stuff from chapter 5.
- Sun Feb 02, 2020 7:34 pm
- Forum: *Organic Reaction Mechanisms in General
- Topic: K meaning
- Replies: 29
- Views: 2016
Re: K meaning
approx 1.380649×10−23 J/K
- Sun Feb 02, 2020 7:28 pm
- Forum: Phase Changes & Related Calculations
- Topic: Why does steam cause burns?
- Replies: 29
- Views: 1079
Re: Why does steam cause burns?
Steam has way more energy than liquid as a result of the energy required to vaporize liquid, and as a result, the phase change releases more energy onto your skin in the form of heat and burns more
- Sun Feb 02, 2020 12:18 am
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Calorimetry
- Replies: 4
- Views: 135
Re: Calorimetry
Does the substance in the bomb calorimeter get heat added to it? In my mind, I feel like that would mess up the measurement of the heat released by the actual reaction. I thought that the experiments in the bomb calorimeter had to spontaneously occur? Bomb calorimeters still require a heat source, ...
- Sun Feb 02, 2020 12:13 am
- Forum: Phase Changes & Related Calculations
- Topic: standard reaction enthalpy vs. standard enthalpy of formation
- Replies: 7
- Views: 1000
Re: standard reaction enthalpy vs. standard enthalpy of formation
standard reaction enthalpy is the enthalpy for the overall reaction while standard enthalpy of formation is the enthalpy of one mole of product formed from its parts
- Sun Feb 02, 2020 12:09 am
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: H and q
- Replies: 7
- Views: 184
Re: H and q
delta h and q are the same at constant pressure.
- Sun Jan 19, 2020 9:16 pm
- Forum: Ideal Gases
- Topic: Kp given instead of Kc
- Replies: 8
- Views: 439
Re: Kp given instead of Kc
Use PV=nRT
- Sun Jan 19, 2020 9:11 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: pKa
- Replies: 13
- Views: 429
Re: pKa
inverse relationship, high Ka, low pka means stronger acid, low Ka, high pka weaker acid
- Sun Jan 19, 2020 9:09 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Relationship between pressure and volume
- Replies: 10
- Views: 357
Re: Relationship between pressure and volume
inversely proportional, and an increase in volume in a system is only recognized if it is the result of change in volume, which is usually assumed unless the problem involves pumping an inert gas into a system
- Sun Jan 19, 2020 9:07 pm
- Forum: Ideal Gases
- Topic: Topics on Test 1
- Replies: 37
- Views: 1202
Re: Topics on Test 1
most certainly outline 1.
- Sun Jan 19, 2020 8:29 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: composite chemical equations
- Replies: 2
- Views: 86
composite chemical equations
can someone explain composite equations, as in hw 5h.3? thanks
- Sun Jan 12, 2020 7:38 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: 5I.13 part c
- Replies: 2
- Views: 67
Re: 5I.13 part c
Thermodynamic stability referring to the relative energy of the closed systems, in which the lowest energy is considered more "thermodynamically" stable.
- Sun Jan 12, 2020 7:33 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Changes in pressure
- Replies: 4
- Views: 222
Re: Changes in pressure
I know that the quick way to explain the changes in pressure is that if the volume decreases and there are more moles of gas on the left, then the reaction proceeds to the right and vice versa. But why is this the short way? If you know that the volume decreases, then you also know that there is st...
- Sun Jan 12, 2020 7:30 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: 5.61
- Replies: 3
- Views: 139
Re: 5.61
we cannot increase the concentration of a pure solid or liquid in an equilibrium expression so it is regarded as equal to 1 and hence ignored in calculation.
- Sun Jan 12, 2020 7:28 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Test 1
- Replies: 6
- Views: 206
Re: Test 1
According to the testing schedule posted on the syllabus, Test 1 should be on 1/21/2020, in discussion section.
- Sun Jan 12, 2020 12:56 pm
- Forum: Ideal Gases
- Topic: converting Kc to Kp
- Replies: 13
- Views: 375
Re: converting Kc to Kp
is it better to convert all values of Kc to Kp before continuing to solve a problem (making an ICE table and so on...) using the ideal gas equation, or is it better to do it as the textbook instructs?
- Sun Dec 01, 2019 7:54 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: ligands
- Replies: 1
- Views: 165
ligands
how do we determine if a ligand is polydentate?
- Sun Dec 01, 2019 7:45 pm
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: sigma bond
- Replies: 11
- Views: 687
Re: sigma bond
A sigma bond is just an area of two orbitals overlapping creating a significant area of electron density.
- Sun Dec 01, 2019 7:41 pm
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: Weak vs. Strong Acids
- Replies: 3
- Views: 77
Re: Weak vs. Strong Acids
Based on disassociation. An acid is strong when it completely dissociates in water, and is weak when it only partially dissociates. Higher or lower acidity is usually relative.
- Sun Dec 01, 2019 7:33 pm
- Forum: *Crystal Field Theory
- Topic: Crystal Field Theory
- Replies: 5
- Views: 959
Re: Crystal Field Theory
Will CTF be of any major significance on the final?
chelating
How do we determine whether or not chelation occurs in a molecule? Thanks
- Sat Oct 19, 2019 1:30 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Hund's rule
- Replies: 5
- Views: 124
Re: Hund's rule
Hund's rule.
- Sat Oct 19, 2019 1:26 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Nodal Planes
- Replies: 10
- Views: 227
Re: Nodal Planes
505316964 wrote:Can someone explain why s has no nodal plane? thanks!
there aren't enough electrons that exist within that orbital to form nodes in which case a plane would form, electrons can exist wherever they want within the spherical s orbital
- Sat Oct 19, 2019 1:22 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Nodal Planes
- Replies: 10
- Views: 227
Re: Nodal Planes
if atoms with more electrons have more places where electrons can be found, why does this also increase the amount of nodal planes in that atom? electrons push each other away, more electrons means more pushing each other way until they shape the orbitals, more orbitals means more chances for nodal...
- Sat Oct 19, 2019 1:19 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Nodal Planes
- Replies: 10
- Views: 227
Re: Nodal Planes
Natalie C 1K wrote:if atoms with more electrons have more places where electrons can be found, why does this also increase the amount of nodal planes in that atom?
electron pair repulsion creates gaps
- Sat Oct 19, 2019 1:15 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Midterm
- Replies: 3
- Views: 77
Re: Midterm
I think it wouldn't hurt to brush up on some general chem just to be safe.
- Sun Oct 13, 2019 11:57 pm
- Forum: Properties of Light
- Topic: Homework
- Replies: 11
- Views: 463
Re: Homework
Anything, in this case, from topic 2 (the quantum world) included in the outline.
- Sun Oct 13, 2019 11:55 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Test 1 [ENDORSED]
- Replies: 107
- Views: 16838
Re: Test 1 [ENDORSED]
all materials were to be provided in discussion.
- Sun Oct 13, 2019 11:53 pm
- Forum: Properties of Light
- Topic: MidTerms and Finals
- Replies: 11
- Views: 367
Re: MidTerms and Finals
Midterms yes, finals TBA.
- Sun Oct 13, 2019 11:52 pm
- Forum: Properties of Light
- Topic: Intensity of Light
- Replies: 2
- Views: 105
Re: Intensity of Light
A higher frequency results in more energy per photon so that each photon has enough energy to eject electrons. Increasing the intensity of light means more photons, more photons with enough energy means more ejected electrons.
- Sun Oct 13, 2019 11:51 pm
- Forum: Properties of Light
- Topic: Wave Frequency
- Replies: 9
- Views: 439
Re: Wave Frequency
I believe that the frequency is the amount of energy per photon according to the wave model.
- Tue Oct 01, 2019 12:33 am
- Forum: Limiting Reactant Calculations
- Topic: How to Find a Mass of A Product
- Replies: 4
- Views: 615
Re: How to Find a Mass of A Product
law of conservation of mass
- Tue Oct 01, 2019 12:28 am
- Forum: Limiting Reactant Calculations
- Topic: Limiting Reactant Calculation post-module question
- Replies: 4
- Views: 132
Re: Limiting Reactant Calculation post-module question
convert to grams
- Tue Oct 01, 2019 12:18 am
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Accuracy vs Precision
- Replies: 10
- Views: 343
Re: Accuracy vs Precision
precision is consistent results while accuracy is how close to the true value we can get.
- Mon Sep 30, 2019 11:57 pm
- Forum: Limiting Reactant Calculations
- Topic: Using mols or grams
- Replies: 4
- Views: 172
Re: Using mols or grams
converting to moles is likely a more reliable strategy and probably just a better habit
- Mon Sep 30, 2019 11:52 pm
- Forum: SI Units, Unit Conversions
- Topic: mol, g.mol and g.mol-1
- Replies: 12
- Views: 925
Re: mol, g.mol and g.mol-1
g.mol-1 is interchangeable with g/mol, the exponent -1 denoting the fraction