Search found 99 matches
- Fri Mar 13, 2020 3:16 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: applications
- Replies: 1
- Views: 113
Re: applications
We can see how reactions would proceed in a cell (spontaneous or not spontaneous) by comparing the ratio of products to reactants.
- Fri Mar 13, 2020 2:38 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: electrode
- Replies: 5
- Views: 78
Re: electrode
The mass of a solid electrode would not impact the solid potential.
- Fri Mar 13, 2020 12:40 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: how to find k
- Replies: 4
- Views: 82
Re: how to find k
In a concentration cell, we would want to find Q. To find Q we would use E = Enot - RT/nF lnQ . Enot will be equal to 0 so as long as you have an E value you can easily find Q.
- Fri Mar 13, 2020 12:36 pm
- Forum: Administrative Questions and Class Announcements
- Topic: ENDGAME Review Session
- Replies: 71
- Views: 3054
Re: ENDGAME Review Session
Thanks for all the review sessions that have helped us along the 14 series!
- Fri Mar 13, 2020 9:15 am
- Forum: Administrative Questions and Class Announcements
- Topic: Test 2
- Replies: 2
- Views: 82
Re: Test 2
As of this point its pretty much the only way to get in contact with them so I'd say yes.
- Thu Mar 12, 2020 12:14 am
- Forum: Administrative Questions and Class Announcements
- Topic: Final
- Replies: 12
- Views: 326
Re: Final
I believe we will submit the test electronically.
- Tue Mar 10, 2020 10:01 pm
- Forum: Administrative Questions and Class Announcements
- Topic: ENDGAME Review Session
- Replies: 71
- Views: 3054
Re: ENDGAME Review Session
Maya Beal Dis 1D wrote:Are all review sessions going to be cancelled?
I'm pretty sure they all will be cancelled.
- Tue Mar 10, 2020 10:00 pm
- Forum: Student Social/Study Group
- Topic: Review Sessions
- Replies: 4
- Views: 176
Re: Review Sessions
I believe Lyndon' s is the only one.
- Tue Mar 10, 2020 9:58 pm
- Forum: Administrative Questions and Class Announcements
- Topic: final exam 2020
- Replies: 2
- Views: 202
Re: final exam 2020
I know the other 14b teacher made the final take home. Also with how things are going right now I don't think we'll have any review sessions.
- Tue Mar 10, 2020 9:57 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: when to use a different C
- Replies: 2
- Views: 118
Re: when to use a different C
Cp and Cv are specifically meant to be used at a constant pressure or a constant volume. The values C=5/2R and C=3/2R correspond to values specifically for ideal gases.
- Mon Mar 09, 2020 10:26 pm
- Forum: General Rate Laws
- Topic: Equations
- Replies: 5
- Views: 103
Re: Equations
I feel that we just have to know what they are and when to use them although knowing how to derive them may end up being useful.
- Mon Mar 09, 2020 1:41 am
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Anode concentration
- Replies: 3
- Views: 67
Re: Anode concentration
To find the anode concentration you use the equation E = -RT/nF * lnQ where Q is the concentration of products over reactants. As long as you know the concentration of the cathode, E cell, and n you should be able to find the anode concentration.
- Mon Mar 09, 2020 1:38 am
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Concentration Cell
- Replies: 5
- Views: 120
Re: Concentration Cell
In a concentration cell your anode and cathode are the same so the Enot value is therefore 0. To create a charge, we use a concentration gradient instead. This gradient generates Volts as a result. We model this as E = -RTln(Q)/nF where Q is the concentration of the products over the concentration o...
- Mon Mar 09, 2020 1:35 am
- Forum: Student Social/Study Group
- Topic: Final Exam Review
- Replies: 4
- Views: 171
Re: Final Exam Review
Im sure lyndon will hold a UA review session for the final. It will probably be announced in class sometime this week.
- Sun Mar 08, 2020 7:23 pm
- Forum: Balancing Redox Reactions
- Topic: Balancing Basic Redox Reactions
- Replies: 6
- Views: 90
Re: Balancing Basic Redox Reactions
It's still the same basic idea as balancing redox reactions in acidic solutions. In basic solutions, however, we use OH- instead of H+. Other than that it follows the same steps as balancing in acidic solutions.
- Sun Mar 08, 2020 7:21 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Cell Diagrams
- Replies: 13
- Views: 256
Re: Cell Diagrams
We use a solid if there are no solids in the cathode or anode.
- Fri Mar 06, 2020 2:53 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Forward and reverse reaction rates
- Replies: 4
- Views: 111
Re: Forward and reverse reaction rates
There is a different rate for both the forward and reverse reactions so we use k and k'.
- Thu Mar 05, 2020 6:42 pm
- Forum: General Science Questions
- Topic: Reducing Math Errors
- Replies: 7
- Views: 233
Re: Reducing Math Errors
Honestly, your best options are just going slowly and practice. Going slow will help reduce the likelihood of errors and plenty of practice with that same calculator will help you get accustomed to the types of questions.
- Thu Mar 05, 2020 6:40 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: K
- Replies: 5
- Views: 119
Re: K
If Ecell >0 then K >1. Similarly, if Ecell < 0, then K < 1.
- Thu Mar 05, 2020 6:40 pm
- Forum: Balancing Redox Reactions
- Topic: Cathode and Anode
- Replies: 24
- Views: 523
Re: Cathode and Anode
A cell can do work whenever Ecell > 0. This will always be the case if the Cathode is greater than the Anode.
- Thu Mar 05, 2020 6:38 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Cell Diagram
- Replies: 6
- Views: 162
Re: Cell Diagram
Cell diagrams can have any state of matter I believe.
- Mon Mar 02, 2020 2:41 am
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Textbook question 6N.3
- Replies: 1
- Views: 77
Re: Textbook question 6N.3
For K and Q we include gases and aq in the products/reactants
- Mon Mar 02, 2020 12:44 am
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: Voltage Signs for Oxidation Reactions
- Replies: 2
- Views: 44
Re: Voltage Signs for Oxidation Reactions
Yes, all you have to do is flip the sign.
- Mon Mar 02, 2020 12:01 am
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Textbook Example
- Replies: 1
- Views: 14
Re: Textbook Example
The Cl- comes from the fact that the Hg2Cl2 is dissociating into both Cl- and Hg.
- Sun Mar 01, 2020 11:58 pm
- Forum: Balancing Redox Reactions
- Topic: Anode and Xathod
- Replies: 9
- Views: 108
Re: Anode and Xathod
The anode is where the oxidation reaction while the cathode is where the reduction reaction occurs. Convention dictates that the anode is on the right in a cell diagram and that the cathode is on the left.
- Sun Mar 01, 2020 11:56 pm
- Forum: Zero Order Reactions
- Topic: Difference
- Replies: 5
- Views: 141
Re: Difference
When we change the concentration of one of the reactants, zero, first and second reactions will all respond differently as to how much product is subsequently formed. The reaction order can tell us how impactful a certain reactant is.
- Sun Mar 01, 2020 11:49 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: n in Equation
- Replies: 6
- Views: 113
Re: n in Equation
When you look at the individual half reactions, n represents the moles of electrons being transferred. This value must be the same for both half reactions.
- Sat Feb 29, 2020 2:00 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: 5g. 13)
- Replies: 3
- Views: 70
Re: 5g. 13)
We don't need to make any assumptions as we know that delta G naught = -RTlnK. As a result, we can just substitute the delta G naught value.
- Tue Feb 25, 2020 8:20 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: 6M.5
- Replies: 4
- Views: 132
Re: 6M.5
We need a solid to be the electrode. As there is no solid on the right hand side, we use Platinum.
- Tue Feb 25, 2020 8:14 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: 6L - Where do you find Estandard values?
- Replies: 2
- Views: 30
Re: 6L - Where do you find Estandard values?
First you have to find what the two individual half rxns are. From there look in Appendix 2B to find the redox potential for the given half reaction. If your two half rxns are one oxidation and one reaction, make sure to multiply the oxidation reaction by a negative 1 and then add the two potentials.
- Tue Feb 25, 2020 8:09 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Platinum electrode
- Replies: 4
- Views: 91
Re: Platinum electrode
I believe its when there are no solids for the anode or cathode you would use Platinum.
- Tue Feb 25, 2020 8:08 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: Where to find Ecell values
- Replies: 15
- Views: 241
Re: Where to find Ecell values
Its in the book at Appendix 2B. (After Chapter 11 but before the answer key)
- Tue Feb 25, 2020 2:05 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Midterm question Q3B
- Replies: 2
- Views: 148
Re: Midterm question Q3B
We know that neutralization reactions produce heat when they occur. We want the most heat released to generate the largest delta T possible. Therefore, we look to see which answer choice has the most moles reacting which ends up making the answer choice B.
- Tue Feb 25, 2020 2:03 pm
- Forum: Balancing Redox Reactions
- Topic: 6L. 7 Part C
- Replies: 1
- Views: 29
Re: 6L. 7 Part C
I believe the presence of the (OH) tells us that is in a basic solution.
- Mon Feb 17, 2020 11:07 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Van't Hoff
- Replies: 6
- Views: 88
Re: Van't Hoff
When using the Van't Hoff equation, we assume standard conditions which means that Pressure is 1 atm.
- Mon Feb 17, 2020 11:06 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Midterm Curve
- Replies: 45
- Views: 652
Re: Midterm Curve
I'm pretty sure he curved 14a at the end of last quarter, but I wouldn't expect him to do as much for 14b.
- Mon Feb 17, 2020 11:05 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Exothermic rxns being spontaneous
- Replies: 5
- Views: 150
Re: Exothermic rxns being spontaneous
Spontaneous reactions are characterized by having a deltaG. When a reaction gives off heat(exothermic) that means that H is negative. Now, unless S is positive, deltaG will be negative as deltaG = deltaH - T(deltaS).
- Mon Feb 17, 2020 11:03 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: deltaG in relation to K
- Replies: 3
- Views: 39
Re: deltaG in relation to K
We know that deltaG = deltaH - T(deltaS), but we also have another equation, where deltaG = -RTlnK and K is the ratio of products to reactants. when K <1 lnK will be negative and thereby deltaG will be negative. If K > 1 then lnK is positive and then deltaG will be positive.
- Sat Feb 08, 2020 11:33 am
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Entropy of the system and surrounding
- Replies: 2
- Views: 51
Re: Entropy of the system and surrounding
Keep in mind if something is giving off heat and thereby lowering its temperature then something else has to take in that heat thereby increasing its temperature. As a result, we end up having two different entropies, one negative and one positive
- Sat Feb 08, 2020 11:31 am
- Forum: Calculating Work of Expansion
- Topic: Units for -PV
- Replies: 5
- Views: 53
Re: Units for -PV
We can use both atm or Pa for pressure. Just keep in mind if you use atm you'll get L*atm which is NOT equal to J and you have to convert using the constant 101.325J/(L*atm)
- Sat Feb 08, 2020 11:28 am
- Forum: Ideal Gases
- Topic: Compressing a gas
- Replies: 5
- Views: 105
Re: Compressing a gas
I can't remember the way he taught it in class, but the way I've always thought about it is the gas mixture is attempting to alleviate the increase in pressure as a result of the compression. Because fewer molecules of gas would mean less pressure, the reaction favors the side with fewer moles of gas.
- Mon Jan 20, 2020 11:30 am
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Delta H
- Replies: 10
- Views: 400
Re: Delta H
To see if something is endothermic r exothermic we look at delta G. If delta G is positive, the reaction is endothermic, but if it is negative the reaction is exothermic.
- Mon Jan 20, 2020 11:27 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Delta G
- Replies: 2
- Views: 26
Re: Delta G
I don't think he'll test on it since it wasn't on the outline. But with Dr. Lavelle the slides are fair game to be on the test so I'd know it just to be sure.
- Mon Jan 20, 2020 11:25 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Solids and Liquids in K
- Replies: 3
- Views: 56
Re: Solids and Liquids in K
Pure solids and liquids hold a value of 1 when calculating K. If you wanted you could add them in there but because their value is 1, it does not change the K value.
- Mon Jan 20, 2020 11:23 am
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: 5% Rule
- Replies: 6
- Views: 129
Re: 5% Rule
Yes it does. If we are to infer that x is a minimal value that does impact the equation we need to know that it is less than 5% in both scenarios.
- Mon Jan 20, 2020 11:21 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Kp units
- Replies: 2
- Views: 47
Re: Kp units
In the end, Kp is unitless. For partial pressures however we use bar.
- Mon Jan 20, 2020 11:20 am
- Forum: Ideal Gases
- Topic: R constant for PV=nRT
- Replies: 7
- Views: 63
Re: R constant for PV=nRT
R is equal to 8.3145 x 10^-2
- Sun Jan 19, 2020 9:08 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: K vs Q
- Replies: 14
- Views: 93
Re: K vs Q
K is the reaction constant and remains the same at every point during the reaction, while Q is the ratio of products to reactants at a given point and can tell us which direction the reaction will proceed in next.
- Sun Jan 19, 2020 9:02 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: X was ignored
- Replies: 27
- Views: 273
Re: X was ignored
Because K is such a small value, < 10^-3, we can assume x will be so small that it is inconsequential. As a result, we ignore the -x in the denominator and solve as if it were not there.
- Sat Jan 18, 2020 10:58 pm
- Forum: Ideal Gases
- Topic: Ideal Gas meaning
- Replies: 7
- Views: 160
Re: Ideal Gas meaning
At low temperatures, most gases are going to act ideally. In this course, we'll probably only deal with ideal gases because this allows for us to apply PV=nRT and infer molecular kinetic energy based on temperature.
- Thu Dec 05, 2019 9:40 pm
- Forum: Properties & Structures of Inorganic & Organic Bases
- Topic: Base Strength
- Replies: 1
- Views: 129
Re: Base Strength
Look for relative anion stability. The more stable the anion, the stronger the base.
- Thu Dec 05, 2019 9:39 pm
- Forum: Lewis Acids & Bases
- Topic: Curiosity's Sake
- Replies: 1
- Views: 93
Re: Curiosity's Sake
If it was a polyprotic base then the conjugate acid of NH3NH3^+ would be NH3NH4^2+
- Thu Dec 05, 2019 9:37 pm
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: Acid Strength
- Replies: 2
- Views: 53
Re: Acid Strength
Look for which would have increased relative anion stability, that should be your stronger acid.
- Thu Dec 05, 2019 9:35 pm
- Forum: Hybridization
- Topic: Determining Hybridization
- Replies: 4
- Views: 65
Re: Determining Hybridization
I believe you can tell by looking at regions of electron density.
- Thu Dec 05, 2019 9:33 pm
- Forum: Polyprotic Acids & Bases
- Topic: Strength of Acids
- Replies: 3
- Views: 119
Re: Strength of Acids
Both anions would have resonance, but Chlorine's higher electronegativity makes the anion more stable. As a result HClO2 is the stronger acid.
- Mon Dec 02, 2019 12:13 am
- Forum: Administrative Questions and Class Announcements
- Topic: Monday's Lecture
- Replies: 2
- Views: 76
Re: Monday's Lecture
I think he'll just be picking up where he left off.
- Sun Dec 01, 2019 7:45 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Studying for final exam
- Replies: 8
- Views: 186
Re: Studying for final exam
I'm planning on just reading the textbook and doing any practice problems they give us/are on the outline.
- Sun Dec 01, 2019 7:40 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Past exams
- Replies: 7
- Views: 214
Re: Past exams
There might be something in the test bank if you want to check it out.
- Sun Dec 01, 2019 7:40 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Studying for the Final Exam
- Replies: 1
- Views: 51
Re: Studying for the Final Exam
I'm sure there will be some final review at some point where we'll be able to get practice problems, but until then you could always redo the problems from the outline.
- Sat Nov 30, 2019 11:40 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Final [ENDORSED]
- Replies: 10
- Views: 752
Re: Final [ENDORSED]
Has Lyndon posted a new final review yet?
- Mon Nov 25, 2019 3:43 pm
- Forum: Lewis Acids & Bases
- Topic: Proton acceptor and proton donor?
- Replies: 33
- Views: 508
Re: Proton acceptor and proton donor?
The Bronsted Acid is the proton donor and the Bronsted Base is the proton acceptor.
- Mon Nov 25, 2019 3:39 pm
- Forum: Naming
- Topic: Focus 9C.3
- Replies: 4
- Views: 36
Re: Focus 9C.3
The Roman Numeral (III) tells us that.
- Sun Nov 24, 2019 4:14 pm
- Forum: General Science Questions
- Topic: Review Sessions for Final
- Replies: 7
- Views: 182
Re: Review Sessions for Final
Dr. Lavelle said he was working to organize rooms for the session in an email, we should probably hear about it in lecture soon.
- Sun Nov 24, 2019 12:58 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Coordination compounds
- Replies: 2
- Views: 38
Re: Coordination compounds
After looking it up, a coordination compound is a central atom or ion (typically a transition metal) surrounded by other molecules or ions known as ligands.
- Sun Nov 24, 2019 12:56 am
- Forum: Bronsted Acids & Bases
- Topic: Bronsted vs. Lewis Acids
- Replies: 4
- Views: 72
Re: Bronsted vs. Lewis Acids
A Bronsted acid is a substance that gives off protons, so the proton donor. A Lewis acid is a substance that can accept a lone pair of electrons. Just because something is a Lewis Acid, does not mean it has to be a Bronsted Acid.
- Mon Nov 18, 2019 8:49 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bonds in VSEPR
- Replies: 11
- Views: 160
Re: Bonds in VSEPR
We're only looking for regions of electron density, so all bonds, lone pairs, or single electrons just count as a singular region.
- Mon Nov 18, 2019 8:47 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Determining polarity 2E 25 pt d
- Replies: 3
- Views: 58
Re: Determining polarity 2E 25 pt d
The only time it could be polar is if one of the X atoms was different so that the dipoles no longer canceled each other out
- Mon Nov 18, 2019 8:42 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Molecular Shape vs. Molecular Geometry
- Replies: 3
- Views: 70
Re: Molecular Shape vs. Molecular Geometry
I believe molecular geometry is the shape of a molecule when taking into consideration lone pairs of electrons while the molecular shape is the shape of the molecule when no taking into account the lone pairs.
- Tue Nov 12, 2019 6:56 am
- Forum: Dipole Moments
- Topic: 3f.1
- Replies: 3
- Views: 60
Re: 3f.1
All of the molecules can have London Dispersion forces. A, C, and D will have dipole-dipole interactions, but only A and C will have Hydrogen bonding.
- Mon Nov 11, 2019 3:31 pm
- Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
- Topic: london forces
- Replies: 6
- Views: 63
Re: london forces
Yes, all molecules do.
- Mon Nov 11, 2019 12:13 pm
- Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
- Topic: hydrogen bonding in water
- Replies: 3
- Views: 46
Re: hydrogen bonding in water
The partial negative charge on the Oxygen is attracted to the partial positive of the Hydrogen. The short lines represent that attraction.
- Mon Nov 11, 2019 11:45 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: Test 2
- Replies: 6
- Views: 120
Re: Test 2
I think it will end up being everything on Outline 4
- Mon Nov 11, 2019 11:42 am
- Forum: General Science Questions
- Topic: Chemitry Series
- Replies: 5
- Views: 142
Re: Chemitry Series
I believe that 14B has a lab that goes with it and I've heard all the organic chemistry courses are hard.
- Mon Nov 11, 2019 11:39 am
- Forum: General Science Questions
- Topic: Chemistry Community Questions
- Replies: 5
- Views: 166
Re: Chemistry Community Questions
I would probably ask you TA about it to see how they're grading you for chem community participation. Hope that helps!
- Mon Nov 11, 2019 11:38 am
- Forum: General Science Questions
- Topic: Midterm
- Replies: 1
- Views: 56
Re: Midterm
I believe that your TA will grade your midterm, and they do have partial credit.
- Mon Nov 11, 2019 11:37 am
- Forum: Administrative Questions and Class Announcements
- Topic: Video Modules
- Replies: 5
- Views: 89
Re: Video Modules
I hope he does because they're a great resource. If not we still have step ups and the workshops to help fill in any gaps of knowledge.
- Sun Nov 03, 2019 9:01 pm
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: Kinetic Energy Uncertainty Conversion
- Replies: 3
- Views: 196
Re: Kinetic Energy Uncertainty Conversion
From what I gather, you know have energy per electron. We know there are 6.022 x 10^23 electrons in a mol. If you divide by Avagadro's number you should get energy per mol.
- Sun Nov 03, 2019 8:58 pm
- Forum: Octet Exceptions
- Topic: Octet Rule exceptions
- Replies: 14
- Views: 390
Re: Octet Rule exceptions
H, He, Li, Be, B, and Al I believe will never have a full octet. Additionally, some elements like Si, P, S, and Cl can have expanded octets. I'm pretty sure we just have to memorize what the exceptions are.
- Sun Nov 03, 2019 8:57 pm
- Forum: Lewis Structures
- Topic: Delocalized Electrons
- Replies: 4
- Views: 36
Re: Delocalized Electrons
As resonance structures show, electrons can group in different manners. Delocalized means it doesn't group in one specific manner/with a single atom but rather with multiple.
- Sun Nov 03, 2019 6:21 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Finding Final n
- Replies: 2
- Views: 63
Re: Finding Final n
102.6 nm would be part of the Lyman series which means n would equal 1.
- Sun Nov 03, 2019 6:18 pm
- Forum: Lewis Structures
- Topic: Octet rule.
- Replies: 2
- Views: 38
Re: Octet rule.
H, He, Li, Be, B, and Al I believe will never have a full octet. Additionally, some elements like Si, P, S, and Cl can have expanded octets.
- Sun Oct 27, 2019 7:58 pm
- Forum: Lewis Structures
- Topic: Choosing the central atom
- Replies: 16
- Views: 261
Re: Choosing the central atom
When choosing the central atom you look for which atom has the lowest ionization energy to be the central atom.
- Sun Oct 27, 2019 7:56 pm
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: Questions with Heisenburg uncertainty principle
- Replies: 2
- Views: 52
Re: Questions with Heisenburg uncertainty principle
delta x is the uncertainty in position as we do not know exactly where an electron is at a given time. Delta p is the uncertainty in momentum which is derived by mass x velocity because we are not sure about the velocity.
- Sun Oct 27, 2019 7:52 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Electron configurations
- Replies: 3
- Views: 57
Re: Electron configurations
To my knowledge, x, y, and z refer to the different electron pairs possible in orbital. There can be 2 electrons per orbital as long as they have opposite spin. In p, for example, there can be up to 6 electrons grouped in twos. To organize them we separate them by Px, Py, and Pz.
- Sun Oct 20, 2019 8:10 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: 1E-11
- Replies: 4
- Views: 72
Re: 1E-11
For sodium, it would look like this: [Ne] 3s^1
If you look at a periodic table, the closest element before Na with a full octet is Neon, so we start with [Ne]. From there, the valence electrons of Na fill up to the 3s^1 so we write that after.
If you look at a periodic table, the closest element before Na with a full octet is Neon, so we start with [Ne]. From there, the valence electrons of Na fill up to the 3s^1 so we write that after.
- Sun Oct 20, 2019 8:04 pm
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: Heisenberg Indeterminacy Equation Confusion
- Replies: 2
- Views: 123
Re: Heisenberg Indeterminacy Equation Confusion
From what I understand, we don't exactly know where an electron is at a given moment so the "x" is similar to probability in the sense that we think the electron should be somewhere in that vicinity. As far as momentum goes, we appear to be calculating linear momentum as it's just mass x v...
- Sun Oct 20, 2019 7:58 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: 1D-15
- Replies: 3
- Views: 49
Re: 1D-15
Principal numbers are your n values while the angular values are your l values. For example for 6p, n = 6 and l = 1.
- Sat Oct 19, 2019 11:35 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Angular Wavefunctions
- Replies: 2
- Views: 48
Angular Wavefunctions
For tests, are we expected to know all of the angular wave function equations for all values of l as seen in topic 1D.2?
- Thu Oct 17, 2019 11:21 pm
- Forum: Einstein Equation
- Topic: 1B.15)
- Replies: 4
- Views: 116
1B.15)
The velocity of an electron that is emitted from a metallic surface by a photon is 3.6 x 10^3 km/s. (a) What is the wavelength of the ejected electron? I've been trying this for some time but I can't seem to get the same answer the book has. How do I tackle it? Edit: Ok I figured it out but why do y...
- Sat Oct 12, 2019 7:34 pm
- Forum: Properties of Electrons
- Topic: Weight of Particles
- Replies: 4
- Views: 60
Re: Weight of Particles
After looking it up, the masses are as follows:
Neutron = 1.6749286*10^-27 kg
Proton = 1.6726231*10^-27 kg
Electron = 9.1093897*10^-31 kg
Neutron = 1.6749286*10^-27 kg
Proton = 1.6726231*10^-27 kg
Electron = 9.1093897*10^-31 kg
- Sat Oct 12, 2019 5:04 pm
- Forum: DeBroglie Equation
- Topic: Resonance
- Replies: 2
- Views: 50
Resonance
I'm not sure if I heard this correctly, but I believe it was briefly mentioned that the De Broglie wave equation applies for any particle that has resonance with momentum. What exactly does it mean to have resonance?
- Sat Oct 12, 2019 3:22 pm
- Forum: Properties of Electrons
- Topic: Measuring wavelike properties
- Replies: 3
- Views: 74
Re: Measuring wavelike properties
In the lecture it was mentioned that anything with a De Broglie wavelength of less than 10^-15 m does not have any detectible wave-like behavior.
- Sat Oct 12, 2019 3:19 pm
- Forum: Properties of Light
- Topic: Intensity of Light
- Replies: 4
- Views: 96
Intensity of Light
So if I understand this correctly, increasing the intensity of light means increasing the number of photons. How exactly are able to increase the number of photons in light?
- Sat Oct 12, 2019 3:13 pm
- Forum: Administrative Questions and Class Announcements
- Topic: When do we need our 5 posts done by?
- Replies: 4
- Views: 127
Re: When do we need our 5 posts done by?
I believe that the posts are due each Sunday as that's how it was last week. To double-check I would suggest shooting your TA an email as they may have a special policy.
Hope this helps!
Hope this helps!
- Wed Oct 02, 2019 10:05 am
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Finding the amount in moles of a part of a molecule
- Replies: 3
- Views: 96
Re: Finding the amount in moles of a part of a molecule
First you'll have to divide the mass of UF6 by the molar mass. This gives you the moles of UF6 present. As there are 6 moles of F- in 1 mol of UF6, multiply the result by 6. This should give you the moles of F- ions.
- Tue Oct 01, 2019 11:30 pm
- Forum: Administrative Questions and Class Announcements
- Topic: using older edition textbook
- Replies: 8
- Views: 164
Re: using older edition textbook
Some questions may be different, but there is a pdf version of the 7th edition textbook in many of the chem 14a facebook messenger groupchats. You can always take a look at that book and compare it to the one you have currently.
- Tue Oct 01, 2019 11:26 pm
- Forum: Limiting Reactant Calculations
- Topic: Limiting Reactant Lecture Question
- Replies: 5
- Views: 179
Re: Limiting Reactant Lecture Question
In theory, I suppose it is possible. To not have any limiting reactants, all the reactants would have to be present in equal moles and be used up at an equivalent rate or as long as all the same moles of each reactant are used up and all of the reactants are used up. This would mean no side reaction...
- Sat Sep 28, 2019 10:11 pm
- Forum: Limiting Reactant Calculations
- Topic: Mass Yield of Product
- Replies: 4
- Views: 113
Re: Mass Yield of Product
You forgot to balance the equation. When you do, the equation shows that 1 mole of C6H9Cl3 will yield 3 moles of AgCl. Thus, the .004 moles C6H9Cl3 should yield .012 moles AgCl. Just remember to convert to grams after!
- Sat Sep 28, 2019 10:03 pm
- Forum: Empirical & Molecular Formulas
- Topic: HW Problem F15
- Replies: 2
- Views: 123
Re: HW Problem F15
I believe the posts are due by next Sunday. As far as the order goes, after looking it up, the Hill System Order is one way to write it, but you may also write it in a manner where the notation indicates structure. For example, this is why you'll see the (OH) group together rather than being split a...