Search found 112 matches
- Sun Mar 15, 2020 8:04 am
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: catalyst vs intermediate
- Replies: 3
- Views: 240
Re: catalyst vs intermediate
An intermediate is formed during one step and used up during another, whereas a catalyst does not get used up.
- Fri Mar 13, 2020 7:27 am
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: 7th Edition Problem 7D.5
- Replies: 3
- Views: 266
Re: 7th Edition Problem 7D.5
The 1.8 comes from doing e^(0.59), which you should do to eliminate the ln from the left side!
- Wed Mar 11, 2020 6:18 pm
- Forum: *Free Energy of Activation vs Activation Energy
- Topic: Activation Energy
- Replies: 9
- Views: 1445
Re: Activation Energy
Activation energy is the amount of energy needed for a specific reaction to occur. When energy input is needed, the reaction is endergonic, and when energy is released, the reaction is exergonic.
- Wed Mar 11, 2020 6:09 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Catalysis
- Replies: 11
- Views: 800
Re: Catalysis
Catalysis results in lowering the activation energy for a reaction to proceed, thus increasing the rate constant.
- Wed Mar 11, 2020 6:07 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Activation Energy and the Rate Constant
- Replies: 4
- Views: 345
Re: Activation Energy and the Rate Constant
When activation energy decreases, the reaction will proceed faster since there is less energy required for molecules to react upon collision, so the rate constant increases.
- Wed Mar 11, 2020 6:05 pm
- Forum: General Science Questions
- Topic: Chemistry Final
- Replies: 16
- Views: 1139
Re: Chemistry Final
CCLE usually has options for a variety of different formats, so I wouldn't count on the exam being all multiple choice.
- Wed Mar 11, 2020 6:01 pm
- Forum: General Rate Laws
- Topic: Rate Determining Step
- Replies: 5
- Views: 336
Re: Rate Determining Step
Yes, the step with the slowest rate is the rate determining step for the reaction!
- Mon Mar 02, 2020 7:02 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Water in Cell Diagrams
- Replies: 2
- Views: 202
Re: Water in Cell Diagrams
Water should always be left out of cell diagrams
- Mon Mar 02, 2020 7:02 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Test Two
- Replies: 5
- Views: 349
Re: Test Two
I think your best bet would be to go to the Peer Learning Sessions for extra help!
- Mon Mar 02, 2020 7:01 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Gibbs free energy equations
- Replies: 5
- Views: 394
Re: Gibbs free energy equations
You mostly will need to use ∆G = -nFE˚and ∆G = -RTlnK, and sometimes a combination of both depending on what the question is asking.
- Mon Mar 02, 2020 7:00 pm
- Forum: Method of Initial Rates (To Determine n and k)
- Topic: determine n
- Replies: 16
- Views: 1363
Re: determine n
n is the number of moles of electrons you have in your half reactions
- Mon Mar 02, 2020 6:58 pm
- Forum: Balancing Redox Reactions
- Topic: Oxidation number of 03
- Replies: 2
- Views: 153
Re: Oxidation number of 03
I'm pretty sure it's 0!
- Thu Feb 27, 2020 5:41 pm
- Forum: Administrative Questions and Class Announcements
- Topic: UA sessions
- Replies: 5
- Views: 312
Re: UA sessions
Most UAs are very helpful in answering questions especially during the drop ins! In the other sessions they usually come with practice questions but are still open to questions from students especially at the end.
- Thu Feb 27, 2020 5:40 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: How to tell which is anode/cathode based on standard reduction potentials E
- Replies: 5
- Views: 329
Re: How to tell which is anode/cathode based on standard reduction potentials E
You want the cell to be spontaneous, so you have to check which number being flipped would result in the more positive number.
- Thu Feb 27, 2020 5:37 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Standard electron potential
- Replies: 2
- Views: 188
Re: Standard electron potential
A larger value of the standard reduction potentials means it is harder for the element to be reduced.
- Thu Feb 27, 2020 5:35 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Drawing Cell Diagram
- Replies: 7
- Views: 479
Re: Drawing Cell Diagram
No, you just need to include the compound and its state
- Thu Feb 27, 2020 5:32 pm
- Forum: General Science Questions
- Topic: Test 2
- Replies: 16
- Views: 951
Re: Test 2
Test 2 will cover the last page of the thermodynamics outline and all of the electrochemistry outline!
- Thu Feb 20, 2020 6:14 pm
- Forum: Balancing Redox Reactions
- Topic: Balancing Redox Reactions
- Replies: 5
- Views: 296
Re: Balancing Redox Reactions
As long as your equation is balanced and you have the reactants and products on their respective sides, you should be fine!
- Thu Feb 20, 2020 6:12 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: salt bridge
- Replies: 5
- Views: 296
Re: salt bridge
The salt bridge allows ions to move between the two solvents, preventing a stop in the flow of electrons due to too high of a charge accumulating in one solvent.
- Thu Feb 20, 2020 6:10 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: calculating E(cell)
- Replies: 2
- Views: 186
Re: calculating E(cell)
Lavelle said that the second method (drawing out the diagram and figuring out which sign needs to be switched) is the better option out of the two we learned.
- Thu Feb 20, 2020 6:09 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: standard hydrogen electrode
- Replies: 3
- Views: 225
Re: standard hydrogen electrode
The SHE can be used to measure the standard reduction potential of different elements.
- Thu Feb 20, 2020 6:09 pm
- Forum: Balancing Redox Reactions
- Topic: Test 2 [ENDORSED]
- Replies: 12
- Views: 649
Re: Test 2 [ENDORSED]
Test 2 is now week 9 and it will cover the rest of outline 4 and all of outline 5
- Thu Feb 13, 2020 7:09 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: equilibrium concentrations
- Replies: 7
- Views: 498
Re: equilibrium concentrations
Concentrations give the molarity, so that would be moles/liter.
- Thu Feb 13, 2020 7:08 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Midterm Curve
- Replies: 45
- Views: 2118
Re: Midterm Curve
Dina 2k wrote:how soon does he usually have it graded and back to us?
For 14A I think we got our exam back around a week and a half after the day of the midterm!
- Thu Feb 13, 2020 7:07 pm
- Forum: Administrative Questions and Class Announcements
- Topic: homework
- Replies: 3
- Views: 186
Re: homework
I think you should be fine with any topic this week because of the midterm!
- Thu Feb 13, 2020 7:05 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Units in Entropy Equation for Volume
- Replies: 5
- Views: 326
Re: Units in Entropy Equation for Volume
The unit for entropy is J/K
- Thu Feb 13, 2020 7:04 pm
- Forum: General Science Questions
- Topic: Tutoring
- Replies: 6
- Views: 378
Re: Tutoring
Office hours during weeks that don't have exams are usually really helpful because you can ask your specific questions!
- Tue Feb 04, 2020 2:27 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Topics on the Midterm
- Replies: 22
- Views: 1020
Re: Topics on the Midterm
I think by the end of this week we will have gone over most of thermodynamics, so the midterm will include outlines 1-4.
- Tue Feb 04, 2020 2:24 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: C = K?
- Replies: 5
- Views: 357
Re: C = K?
Even though the units are different, an increase of 1 unit Kelvin is equivalent to an increase of 1 unit Celsius. Since this equation uses delta T rather than just T, you can use the same number without having to do any conversions.
- Tue Feb 04, 2020 2:22 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Midterm
- Replies: 6
- Views: 306
Re: Midterm
Many of the constants and equations we use will be given, but there are also some that I think we will just be expected to know. I would focus on the ones Lavelle spent the most time on in lecture and also be sure to understand the relationships between all of the different equations.
- Mon Feb 03, 2020 11:06 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: endo vs exo
- Replies: 8
- Views: 175
Re: endo vs exo
Forming a bond releases energy and therefore is exothermic, while breaking a bond requires an input of energy and therefore is endothermic.
- Tue Jan 28, 2020 11:40 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Order of homework for Thermochem unit
- Replies: 6
- Views: 307
Re: Order of homework for Thermochem unit
In discussion section for this week, my TA went over 4D and 4E topics.
- Tue Jan 28, 2020 11:40 pm
- Forum: Phase Changes & Related Calculations
- Topic: Units
- Replies: 16
- Views: 768
Re: Units
The two are interchangeable here because we only look at temperature in terms of how it changes, and one unit kelvin is equivalent to one unit celsius.
- Tue Jan 28, 2020 11:39 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Best Method of the 3 Given?
- Replies: 7
- Views: 218
Re: Best Method of the 3 Given?
Using bond enthalpies is the least accurate because the values used are averages, so they are not always reliable for the specific molecule in a given question.
- Tue Jan 28, 2020 11:37 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Homework sections
- Replies: 7
- Views: 275
Re: Homework sections
Lavelle seems to be working backwards through this topic. We have covered at least 4D and 4E as of now.
- Tue Jan 28, 2020 11:34 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Test One
- Replies: 2
- Views: 98
Re: Test One
Your TA will pass back your test during discussion section this week!
- Mon Jan 20, 2020 7:01 pm
- Forum: Student Social/Study Group
- Topic: Test 1
- Replies: 9
- Views: 546
Re: Test 1
There isn't a practice test posted but going through the assigned homework problems is usually a good way to get practice!
- Mon Jan 20, 2020 6:59 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Writing K Expression
- Replies: 6
- Views: 210
Re: Writing K Expression
If H2O is a gas in a given question, you should use it in your calculations for K or Q.
- Mon Jan 20, 2020 6:58 pm
- Forum: Student Social/Study Group
- Topic: test 1
- Replies: 7
- Views: 199
Re: test 1
The free response questions are usually similar to the homework questions assigned and examples done in class!
- Mon Jan 20, 2020 6:55 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Module
- Replies: 4
- Views: 187
Re: Module
Calculating Q requires molarity, not moles, so you need to divide by the volume to get the correct values!
- Mon Jan 20, 2020 6:54 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Coverting Kp to Kc
- Replies: 2
- Views: 88
Re: Coverting Kp to Kc
I don't think you will need to do that, you should just use it in whatever form it is given to you and as long as you stay consistent it should get you the correct answer!
- Sun Jan 19, 2020 7:48 pm
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: Problem 12.69
- Replies: 8
- Views: 2869
Re: Problem 12.69
Rosa Munoz 2E wrote:I am confused as well on why you can use the Kb value for NH3
You can use the Kb value for NH3 to find the Ka value of NH4Cl because they are a conjugate acid/base pair
- Wed Jan 15, 2020 9:06 am
- Forum: Administrative Questions and Class Announcements
- Topic: Test 1
- Replies: 7
- Views: 200
Re: Test 1
Test 1 will probably cover Outlines 1 and 2 on his website!
- Wed Jan 15, 2020 9:03 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Autoprotolysis
- Replies: 8
- Views: 191
Re: Autoprotolysis
Autoprotolysis is the naturally occurring transfer of protons between the same type of molecule.
- Wed Jan 15, 2020 9:02 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: When to approximate
- Replies: 5
- Views: 119
Re: When to approximate
If the percent protonation is less than 5%, you can assume that your approximation was appropriate.
- Wed Jan 15, 2020 8:58 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: ICE charts on tests/exams
- Replies: 8
- Views: 236
Re: ICE charts on tests/exams
I would say it's always better to show extra work rather than not enough!
- Wed Jan 15, 2020 8:57 am
- Forum: Administrative Questions and Class Announcements
- Topic: Study Guide Test One
- Replies: 17
- Views: 601
Re: Study Guide Test One
I don't think so, but the outlines are good resources to use while studying!
- Wed Jan 08, 2020 6:11 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: K for Gases
- Replies: 12
- Views: 341
Re: K for Gases
When the reaction is dealing with gases, I believe you should use Kp.
- Wed Jan 08, 2020 6:10 pm
- Forum: Ideal Gases
- Topic: Solids and Liquids
- Replies: 7
- Views: 399
Re: Solids and Liquids
During lecture, Lavelle said solids are excluded because they don't have molar concentrations, and liquids are excluded because the solvent concentration stays the same.
- Wed Jan 08, 2020 6:07 pm
- Forum: Student Social/Study Group
- Topic: Discussion Sections
- Replies: 7
- Views: 385
Re: Discussion Sections
Yes, there are discussion sections during Week 1.
- Wed Jan 08, 2020 6:06 pm
- Forum: Ideal Gases
- Topic: R constant in PV=nRT
- Replies: 9
- Views: 252
Re: R constant in PV=nRT
I think the gas constant will be given to us either in the question or on an equation sheet!
- Tue Jan 07, 2020 4:06 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Homework 1
- Replies: 18
- Views: 581
Re: Homework 1
Since some sections are earlier in the week, week 1 homework is due to your ta at the end of lecture on Friday.
- Sat Dec 07, 2019 10:58 am
- Forum: Bronsted Acids & Bases
- Topic: HCl vs HClO
- Replies: 2
- Views: 253
Re: HCl vs HClO
I think this is because the conjugate base of HCl is more stable than that of HClO.
- Wed Dec 04, 2019 8:34 am
- Forum: Bronsted Acids & Bases
- Topic: Acids and Bases
- Replies: 2
- Views: 125
Re: Acids and Bases
Nawal Dandachi 3G wrote:Acetic acid is a stronger acid because it is stabilized by resonance.
So for this question you would have to draw out the lewis structure to determine if there is resonance and if there is then that one is stronger?
- Wed Dec 04, 2019 8:31 am
- Forum: Bronsted Acids & Bases
- Topic: CaO
- Replies: 10
- Views: 1502
Re: CaO
305416361 wrote:CaO is a strong base because it fully dissociates into its constituent components
Is this just something we would have to memorize? How do we know if it will completely dissociate in water?
- Mon Dec 02, 2019 8:18 am
- Forum: Industrial Examples
- Topic: What do we need to know?
- Replies: 15
- Views: 1528
Re: What do we need to know?
I think overall it would be a good idea to understand the details of specific biological examples from class because he spent a good amount of time going into some of those examples pretty thoroughly.
- Mon Dec 02, 2019 8:17 am
- Forum: Administrative Questions and Class Announcements
- Topic: Lavelle review sessions
- Replies: 3
- Views: 167
Re: Lavelle review sessions
He might go over some previous test questions like he did for the midterm, but other than that I think review sessions for the final will be similar to how they were for the midterm.
- Mon Dec 02, 2019 8:16 am
- Forum: Administrative Questions and Class Announcements
- Topic: Chemistry Community Posts
- Replies: 10
- Views: 603
Re: Chemistry Community Posts
I think different TAs do it differently, but by the end of the quarter all of your points should be added in.
- Mon Dec 02, 2019 8:15 am
- Forum: Administrative Questions and Class Announcements
- Topic: Calculators on Final
- Replies: 6
- Views: 345
Re: Calculators on Final
I'm pretty sure we'll need our calculators during the final, especially for pre-midterm concepts that were very calculation heavy.
- Mon Dec 02, 2019 8:14 am
- Forum: Student Social/Study Group
- Topic: Final topics
- Replies: 10
- Views: 511
Re: Final topics
The exam is cumulative, but may focus more on topics post midterm since we've already been tested on previous concepts on the midterm.
- Mon Nov 25, 2019 8:17 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: minimum coordination number
- Replies: 2
- Views: 175
Re: minimum coordination number
I think it's possible, but it isn't very common.
- Mon Nov 25, 2019 8:13 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bond Angle of Single Electron of A Free Radical
- Replies: 4
- Views: 1061
Re: Bond Angle of Single Electron of A Free Radical
I think we are supposed to consider a radical the same as a lone pair, it's one region of electron density.
- Mon Nov 25, 2019 8:09 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: brackets
- Replies: 13
- Views: 618
Re: brackets
The bracket signifies a coordination sphere.
Re: Naming
I believe we need to know how do do it because one of the objectives on Outline 5 is "Be familiar with the rules for naming coordination compounds."
- Mon Nov 25, 2019 8:04 am
- Forum: Student Social/Study Group
- Topic: Test 2 and Final
- Replies: 18
- Views: 857
Re: Test 2 and Final
205150314 wrote:Does anyone know if we will get some sort of study tools again?
I'm sure Lavelle will be coordinating review sessions like he did for the midterm.
- Thu Nov 21, 2019 1:10 am
- Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
- Topic: Ordering Intermolecular Forces Clarification
- Replies: 2
- Views: 108
Re: Ordering Intermolecular Forces Clarification
Dipole dipole is the strongest, followed by dipole induced dipole. London dispersion forces are the weakest, but if you have a lot of them they can add up and be strong.
- Thu Nov 21, 2019 1:06 am
- Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
- Topic: Carbon Monoxide
- Replies: 3
- Views: 479
Re: Carbon Monoxide
Oxygen is more electronegative than carbon, so there will be a dipole moment there which should make this molecule polar.
- Thu Nov 21, 2019 1:04 am
- Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
- Topic: Homework 3F3
- Replies: 5
- Views: 329
Re: Homework 3F3
Any time the central atom is surrounded by two or more different atoms in a tetrahedral, there will be dipole dipole forces.
- Thu Nov 21, 2019 1:00 am
- Forum: Hybridization
- Topic: for test 2
- Replies: 7
- Views: 234
Re: for test 2
No, hybridization will not be on test 2!
- Mon Nov 18, 2019 9:00 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: AXE notation
- Replies: 10
- Views: 619
Re: AXE notation
Knowing this formula will help you identify the shape and geometry more easily than trying to do individual molecules!
- Wed Nov 13, 2019 8:26 am
- Forum: Lewis Structures
- Topic: Biradical
- Replies: 2
- Views: 207
Re: Biradical
Lavelle touched on this very very briefly so I don't think we are expected to know any details about this concept.
- Wed Nov 13, 2019 8:23 am
- Forum: Polarisability of Anions, The Polarizing Power of Cations
- Topic: Polarizing Power
- Replies: 4
- Views: 378
Re: Polarizing Power
Many different ions may have the same charge, so at that point you can use the size to determine polarizing power. Smaller = more polarizing power.
- Wed Nov 13, 2019 8:21 am
- Forum: Electronegativity
- Topic: Ionization Energy vs. Electronegativity
- Replies: 9
- Views: 9576
Re: Ionization Energy vs. Electronegativity
Both have similar periodic table trends, increasing as you move to the top right corner.
- Wed Nov 13, 2019 8:20 am
- Forum: Bond Lengths & Energies
- Topic: Homework for week 7
- Replies: 5
- Views: 306
Re: Homework for week 7
I think questions from the end of the Chemical Bonds outline should be fine. However, it might be more beneficial to do questions on the next outline.
- Wed Nov 13, 2019 8:14 am
- Forum: Administrative Questions and Class Announcements
- Topic: Homework for week 7
- Replies: 3
- Views: 270
Re: Homework for week 7
I think problems from the last sections of the Chemical Bonds outline should be fine for this week!
- Wed Nov 06, 2019 8:16 am
- Forum: General Science Questions
- Topic: Midterm: Paramagnetic and Diamagnetic
- Replies: 1
- Views: 112
Re: Midterm: Paramagnetic and Diamagnetic
I don't think we need to know these terms since Lavelle never mentioned them.
- Tue Nov 05, 2019 11:01 pm
- Forum: Trends in The Periodic Table
- Topic: Midterm Review Problem 10 d
- Replies: 5
- Views: 461
Re: Midterm Review Problem 10 d
Oxygen has a lower ionization energy than Nitrogen because of the 4th electron joining. Having 2 electrons in the same orbital increases the electron repulsion, making Oxygen more likely to want to give up an electron.
- Tue Nov 05, 2019 10:58 pm
- Forum: Dipole Moments
- Topic: Dipole, midterm?
- Replies: 7
- Views: 455
Re: Dipole, midterm?
I'm pretty sure we'll just be asked to draw the dipole moment on a Lewis structure, which is just adding an arrow that points in the direction the electron is moving.
- Tue Nov 05, 2019 10:50 pm
- Forum: Properties of Electrons
- Topic: Work Function
- Replies: 4
- Views: 259
Re: Work Function
A lot of the practice questions convert it to J/mol so that's probably your best bet. Just make sure your units cancel out while you're doing the equations and you should be fine.
- Tue Nov 05, 2019 10:48 pm
- Forum: Photoelectric Effect
- Topic: Light acts as a wave
- Replies: 4
- Views: 401
Re: Light acts as a wave
The photoelectric effect tells us that light is quantized into packets of energy (photons). De Broglie's equation is the one that supports the idea of electrons being able to have wave like properties!
- Mon Nov 04, 2019 1:03 pm
- Forum: Administrative Questions and Class Announcements
- Topic: KAREN SUN 5-7PM WORKSHOP - DOWNLAOD WORKSHEETS HERE
- Replies: 53
- Views: 5707
Re: KAREN SUN 5-7PM WORKSHOP - DOWNLAOD WORKSHEETS HERE
Chem_Mod wrote:Here is the key for worksheet on the quantum world.
Is there a different key with the answers to the last two questions on this worksheet? This answer key only has up until question 6 and I wanted to check my answers for number 7 and 8 on the worksheet!
- Mon Nov 04, 2019 9:08 am
- Forum: *Shrodinger Equation
- Topic: Schrodinger relationships
- Replies: 4
- Views: 293
Re: Schrodinger relationships
Schrodinger’s equation uses a wave function to describe an electron because of its wavelike properties and indeterminacy in momentum and position. The wave function represents the orbital (position) that and electron can be found. Do we just have to know the concepts behind Schrodinger's equation? ...
- Mon Nov 04, 2019 9:04 am
- Forum: Electronegativity
- Topic: Trend of Electronegativity
- Replies: 22
- Views: 2022
Re: Trend of Electronegativity
Electronegativity increases up the periodic table and towards the right. Fluorine is the most electronegative element.
- Mon Nov 04, 2019 9:03 am
- Forum: Dipole Moments
- Topic: Dipole Arrow
- Replies: 5
- Views: 236
Re: Dipole Arrow
During lecture, Lavelle said an easy way to remember the direction of the arrow is that it's pointing in the direction that the electron is moving.
- Wed Oct 30, 2019 9:03 am
- Forum: Lewis Structures
- Topic: Resonance
- Replies: 4
- Views: 92
Re: Resonance
In addition to the previously given definitions, Lavelle also mentioned in class that resonance leads to more stable and less reactive molecules because it results in multiple bond characteristics being spread out throughout a molecule, lowering its energy.
- Wed Oct 30, 2019 8:57 am
- Forum: Ionic & Covalent Bonds
- Topic: 2A.5 (d-block configurations)
- Replies: 4
- Views: 158
Re: 2A.5 (d-block configurations)
For ions, it's easiest to first write out the regular electron configuration and then add or take away electrons depending on the charge. Since full and half filled d shells are more stable, those should be filled before the 4s. For Cu, the electron configuration is [Ar] 3d104s1, and when the charge...
- Wed Oct 30, 2019 8:53 am
- Forum: Ionic & Covalent Bonds
- Topic: Atomic and ionic radii
- Replies: 3
- Views: 194
Re: Atomic and ionic radii
The atomic radius is half the diameter of a neutral atom, measuring across the outer electrons. The ionic radius is half the distance between two gas atoms that are joined by an ionic bond. Both generally have the same periodic table trend: radius decreases moving across a period and increases movin...
- Wed Oct 30, 2019 8:49 am
- Forum: Octet Exceptions
- Topic: List of Octet exceptions
- Replies: 6
- Views: 293
Re: List of Octet exceptions
Usually, non-metals with a d-subshell can have expanded octets because there are more spaces for electrons to fill
- Tue Oct 29, 2019 10:59 am
- Forum: Lewis Structures
- Topic: Drawing Lewis Structures
- Replies: 4
- Views: 194
Re: Drawing Lewis Structures
I think it would be best to play it safe and draw the structure with the lower formal charge because that is the one that is most stable and most likely to be an accurate representation.
- Tue Oct 29, 2019 10:52 am
- Forum: Ionic & Covalent Bonds
- Topic: Study For midterm
- Replies: 7
- Views: 314
Re: Study For midterm
I think homework questions would be the most efficient way to study because practicing the same types of questions as the exam will have will be a good way to prepare!
- Mon Oct 21, 2019 10:06 am
- Forum: *Black Body Radiation
- Topic: electromagnetic radiation 2
- Replies: 4
- Views: 561
Re: electromagnetic radiation 2
Energy and wavelength are inversely proportional. Radio waves are longer, so they have less energy than UV.
- Mon Oct 21, 2019 10:04 am
- Forum: Photoelectric Effect
- Topic: Threshold Energy
- Replies: 7
- Views: 488
Re: Threshold Energy
I believe that saying there is 0 KE means that after the electron has been ejected, there is no excess energy leftover that would be considered Kinetic Energy. When the energies match up, all of it is used to eject the electron so there will be 0 KE.
- Mon Oct 21, 2019 9:59 am
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Probability of finding an electron at a certain location
- Replies: 4
- Views: 241
Re: Probability of finding an electron at a certain location
In the textbook chapters, I believe this concept only came up when referencing where electrons had 0 density or a "nonzero density." Since there weren't any homework questions assigned, I don't anticipate needing to know too many details about this concept!
- Mon Oct 21, 2019 9:52 am
- Forum: Student Social/Study Group
- Topic: Week 4 HW Problems
- Replies: 7
- Views: 286
Re: Week 4 HW Problems
I think most TAs are flexible about what homework you turn in! As long as the material is recent, I think you should be fine.
- Mon Oct 21, 2019 9:48 am
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Short Hand or Normal Way?
- Replies: 3
- Views: 207
Re: Short Hand or Normal Way?
I think he will specify! However, when going through them in class he usually defaulted to using the shorthand, so I would expect that to be what's asked of us on the exams unless specified otherwise.
- Mon Oct 21, 2019 9:47 am
- Forum: Quantum Numbers and The H-Atom
- Topic: Spin and orbitals
- Replies: 4
- Views: 113
Re: Spin and orbitals
I believe Dr.Lavelle said it was because at that point in energy levels, electron repulsion comes into play so it's more stable to have parallel spins before filling in the paired spin electrons
- Thu Oct 17, 2019 1:13 pm
- Forum: DeBroglie Equation
- Topic: Constant Question
- Replies: 7
- Views: 309
Re: Constant Question
I don't think it will change your answer too much, but if you're rounding at multiple steps during the process then your final answer won't be as accurate as it could. If possible, I would avoid rounding as much as possible until getting to the final step.
- Mon Oct 14, 2019 8:09 am
- Forum: Student Social/Study Group
- Topic: Best Sessions
- Replies: 12
- Views: 424
Re: Best Sessions
The Step-Up sessions in Covel that I have gone to have had about 15 students and 1 LA leading and going through practice problems. They do a really good job of breaking the questions down so if you're struggling with a topic or just want extra clarification, those would be great resource. However, i...
- Mon Oct 14, 2019 8:02 am
- Forum: Properties of Light
- Topic: Angstrom
- Replies: 10
- Views: 462
Re: Angstrom
I think the units will be clarified in the questions. If they aren't, I would probably stick to one of the more conventional ones such as m or nm!
- Mon Oct 14, 2019 8:00 am
- Forum: Properties of Light
- Topic: MidTerms and Finals
- Replies: 11
- Views: 390
Re: MidTerms and Finals
I believe the midterm and final are both outside of class/section hours! There is "Test and Exam Schedule" on Lavelle's website with details for both.