Search found 88 matches
- Wed Mar 13, 2019 3:13 pm
- Forum: Second Order Reactions
- Topic: Units
- Replies: 4
- Views: 554
Re: Units
In total the rate should be in M/s, but k will have units of 1/M*s
- Wed Mar 13, 2019 3:12 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: Molecularity
- Replies: 2
- Views: 540
Re: Molecularity
Think of the order of the reaction when determining molecularity.
- Wed Mar 13, 2019 3:11 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: E˚ vs E
- Replies: 13
- Views: 15792
Re: E˚ vs E
E* refers to cell potential at standard conditions, it does NOT change with amount of substance. E is just the potential of the cell under ANY conditions.
- Mon Mar 11, 2019 12:42 pm
- Forum: Zero Order Reactions
- Topic: Zero Order Reaction
- Replies: 5
- Views: 893
Re: Zero Order Reaction
An example I like to think of is having to reactants, A and B, and a few different experiments changing the concentrations of each, and analyzing the change in the rate. When A is increased, let's say that the reaction shows no change. You do the same for B, still no change. I think of zero order as...
- Wed Mar 06, 2019 8:51 pm
- Forum: First Order Reactions
- Topic: Units
- Replies: 3
- Views: 409
Re: Units
Your end goal is to have all units b in M/s. With this, you can figure out what the order of the reaction is and adjust k units to reach that end goal units.
- Wed Mar 06, 2019 12:06 pm
- Forum: Van't Hoff Equation
- Topic: Temp Units
- Replies: 11
- Views: 1366
Re: Temp Units
It would be in K. Think about the units for R! They all need to cancel out
- Tue Mar 05, 2019 10:23 am
- Forum: General Rate Laws
- Topic: Order Reaction/Rate Law
- Replies: 3
- Views: 450
Re: Order Reaction/Rate Law
Use the rate law, and add up the exponents of each reactant.
- Mon Mar 04, 2019 10:25 pm
- Forum: First Order Reactions
- Topic: Half life first order reaction rate
- Replies: 1
- Views: 273
Re: Half life first order reaction rate
We haven't really been taught this yet. We JUST finished our first order work, so we should wait for Dr. Lavelle to actually cover this in lecture.
- Mon Mar 04, 2019 10:23 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Week 9 HW
- Replies: 6
- Views: 671
Re: Week 9 HW
Just stick with kinetics. I do recommend practicing the electrochem problems not included on the test just to stay sharp.
- Mon Mar 04, 2019 10:22 pm
- Forum: General Rate Laws
- Topic: Units of Rate Constant
- Replies: 4
- Views: 513
Re: Units of Rate Constant
In a zero order reaction, the rate constant would just be M*s^-1. With a first order reaction, we'd have just s^-1, as we'd have M from our reactant. In second order we have M^-1*s^-1, and from every unit jump forwards, we have a higher number of M, which is just our order # - 1.
- Mon Feb 25, 2019 10:26 pm
- Forum: Balancing Redox Reactions
- Topic: Gibbs free energy
- Replies: 1
- Views: 226
Re: Gibbs free energy
If you look over some of the equations in your constants and equations sheet, you can see some overlap with dGnought and dEnought. With these equations you can mix and match in other equations in terms of one or the other.
- Mon Feb 25, 2019 10:22 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: MnO4-
- Replies: 1
- Views: 238
Re: MnO4-
O has a charge of -2, so for of those is 8- charge total. Because the combination of Mn and O4 is -, Mn must be 7+ so when those charges are added together it matches what's given.
- Mon Feb 25, 2019 7:24 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Question 6N.1 B 7th Edition
- Replies: 1
- Views: 240
Question 6N.1 B 7th Edition
Does the solutions manual have an error for this problem? It states that the half reaction for In3+ to In2+ is
In3+ + 2e- --> In2+
This causes the Nernst Equation to use 2 for n, when it should just be one right?
In3+ + 2e- --> In2+
This causes the Nernst Equation to use 2 for n, when it should just be one right?
- Mon Feb 25, 2019 6:12 pm
- Forum: Balancing Redox Reactions
- Topic: Friday Lecture Example [ENDORSED]
- Replies: 2
- Views: 343
Re: Friday Lecture Example [ENDORSED]
Also, Fe has no phase change, so Pt is necessary as a solid electrode in the diagram cathode side.
- Mon Feb 25, 2019 6:03 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: n value
- Replies: 11
- Views: 959
Re: n value
I believe n can be the change of moles in the equation or the number of electrons transferred.
- Sun Feb 24, 2019 9:35 pm
- Forum: Balancing Redox Reactions
- Topic: Salt Bridges-won't they dissolve?
- Replies: 5
- Views: 812
Re: Salt Bridges-won't they dissolve?
The salt bridge isn't actually made up of salt itself. It's tubing with gel inside to provide electrical contact between the anode and the cathode.
- Sun Feb 24, 2019 9:33 pm
- Forum: Balancing Redox Reactions
- Topic: Mnemonic for Redox
- Replies: 5
- Views: 1019
Re: Mnemonic for Redox
Are you thinking about LEO and GER?
Lose Electron Oxidation
Gain Electron Reduction?
Lose Electron Oxidation
Gain Electron Reduction?
- Fri Feb 22, 2019 12:05 am
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Delta G = 0
- Replies: 4
- Views: 429
Re: Delta G = 0
Reaction is at physical equilibrium, generally =0 at phase changes!
- Wed Feb 20, 2019 8:18 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Gibbs concept
- Replies: 7
- Views: 757
Re: Gibbs concept
Danny Elias Dis 1E wrote:Can someone explain what is happening on a physical level when deltaG = 0 (the Gibbs free energy is at equilibrium)?
The reaction is at physical equilibrium, and most likely going through a phase change.
- Tue Feb 19, 2019 3:38 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: What to do when temperature isn't given
- Replies: 8
- Views: 905
Re: What to do when temperature isn't given
If it's stated to be in standard conditions. If a temperature is given, use that.
- Tue Feb 19, 2019 12:57 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Delta G a state function?
- Replies: 23
- Views: 2865
Re: Delta G a state function?
Aidan Ryan 1B wrote:What are things we have learned that are not state functions?
Work is NOT a state function because it depends on the path taken to get to the final result.
- Tue Feb 19, 2019 12:56 pm
- Forum: General Rate Laws
- Topic: test 3
- Replies: 6
- Views: 642
Re: test 3
"Test 2 covers all topics on Gibbs free energy and electrochemistry up to but not including the Nernst equation (which is all the new material covered in class Weeks 6 and 7). Test 2 starts Tuesday of Week 8."
Word for word from website. This will 100% be what we're tested on
Word for word from website. This will 100% be what we're tested on
- Mon Feb 18, 2019 4:53 pm
- Forum: Van't Hoff Equation
- Topic: Concept behind Van't Hoff Equation
- Replies: 5
- Views: 706
Re: Concept behind Van't Hoff Equation
This equation helps us determine how a system behaves at equilibrium at a new temperature. The value of K itself changes, so you can really see if products or reactants are favored more or less than they were before!
- Mon Feb 18, 2019 4:50 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Delta G vs. Delta G (degree sign)
- Replies: 4
- Views: 2712
Re: Delta G vs. Delta G (degree sign)
It's just the difference between standard conditions and specific conditions for a system.
- Mon Feb 18, 2019 4:47 pm
- Forum: Calculating Work of Expansion
- Topic: Units for R
- Replies: 10
- Views: 1402
Re: Units for R
These units vary. Always write out your units for calculations, just so you know what R value is needed to solve. In order to get the write answer you need to use the correct R based off of what's asked for and what units are given.
- Mon Feb 18, 2019 4:46 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Calculating Gibbs Free Energy Equations
- Replies: 2
- Views: 321
Re: Calculating Gibbs Free Energy Equations
Both of these methods work! In the end it's all a state function so your path is up to you. With these problems just try to make the most out of what's GIVEN to you.
- Wed Feb 13, 2019 8:59 pm
- Forum: Phase Changes & Related Calculations
- Topic: ΔH vs ΔU?
- Replies: 8
- Views: 1404
Re: ΔH vs ΔU?
Yes at constant pressure. If there is no net change in moles, there will be no work done. So there is the potential for deltaU=deltaH.
- Wed Feb 13, 2019 8:58 pm
- Forum: General Science Questions
- Topic: Midterm Formulas
- Replies: 6
- Views: 995
Re: Midterm Formulas
Everything on the constants and equations sheet will be provided. I don't think EVERY formula is on that, so be sure to know them all.
- Mon Feb 11, 2019 12:31 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Bond enthalpies
- Replies: 10
- Views: 922
Re: Bond enthalpies
Lewis structures ARE helpful for figuring out exactly what is being broken, but it is still possible to solve these problems just by looking at the differences between the reactants and products side.
- Mon Feb 11, 2019 12:30 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Hess's Law
- Replies: 5
- Views: 539
Re: Hess's Law
The test will most likely provide these reactions, but I think knowing the general format of a combustion reaction could come in handy!
- Mon Feb 11, 2019 12:29 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Homework during midterm week [ENDORSED]
- Replies: 5
- Views: 481
Re: Homework during midterm week [ENDORSED]
I recommend doing any thermodynamic problems, as that's what was most recently covered.
- Wed Feb 06, 2019 6:00 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Degenerate states and volume
- Replies: 1
- Views: 162
Re: Degenerate states and volume
Because there was a certain amount of degenerate states in the initial volume, doubling said volume would double the positions molecules can take. Because there's more volume, there's more space/positions to fill, in fact, it's DOUBLE.
- Wed Feb 06, 2019 5:56 pm
- Forum: Calculating Work of Expansion
- Topic: Integral Expression for Work
- Replies: 4
- Views: 506
Re: Integral Expression for Work
The integral equation applies to reversible work, where P is not a constant. Use it if stated to be reversible. Use w=-PdeltaV if it's irreversible.
- Wed Feb 06, 2019 5:54 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Do we have discussion on the day of the midterm?
- Replies: 2
- Views: 281
Re: Do we have discussion on the day of the midterm?
I believe the schedule carries out as normal, unless there's a conflict of timing.
- Tue Feb 05, 2019 11:27 am
- Forum: Calculating Work of Expansion
- Topic: Work vs Degeneracy
- Replies: 2
- Views: 359
Re: Work vs Degeneracy
Work is a lower case w and degeneracy is a capital W. They appear to be separate from each other, and not have much influence on one another. (I may be wrong about that, but w and W are still different)
- Tue Feb 05, 2019 11:19 am
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Entropy
- Replies: 2
- Views: 284
Re: Entropy
Delta U and delta H do not fully describe the system without entropy. Entropy is the likelihood (probability) a system will be in a particular start. The combination of delta U delta h and entropy can give more information as to how the system will change.
- Wed Jan 30, 2019 7:28 pm
- Forum: Calculating Work of Expansion
- Topic: 4A.3 7th Ed
- Replies: 6
- Views: 542
Re: 4A.3 7th Ed
I believe we'll learn how to do this in an upcoming lecture. Don't stress yourself out over it just yet! I'm certain we'll be taught how to do this, if not the book and chemistry community will surely help!
- Tue Jan 29, 2019 10:59 am
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Heat Capacity
- Replies: 5
- Views: 504
Re: Heat Capacity
This honestly depends on the question being asked. Given units and a period table, you should be able to know whether to convert or not to match the question. Just read carefully and fully understand what's being asked for and how you will get there.
- Tue Jan 29, 2019 10:57 am
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Bond Enthalpies
- Replies: 7
- Views: 694
Re: Bond Enthalpies
Diatomic bond enthalpies tend to be accurate, however every other molecule/bond in a chemical reaction has bond enthalpies made up of an average of thousands of different measurements. This averaging makes it inaccurate.
- Mon Jan 28, 2019 10:51 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Breaking Bonds
- Replies: 4
- Views: 379
Re: Breaking Bonds
I recommend drawing all lewis structures out and observe what has changed. Visually seeing it helps a lot.
- Mon Jan 28, 2019 10:50 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Cv and Cp
- Replies: 3
- Views: 397
Re: Cv and Cp
It will most likely be made clear whether or not it's constant pressure or constant volume. I believe the type of calorimeter will be said two, so know how to distinguish them.
- Fri Jan 25, 2019 6:02 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Seventh Edition ? 4A.9
- Replies: 1
- Views: 218
Re: Seventh Edition ? 4A.9
I don't think we learned this in class yet. Would be best to not stress and put it aside until we're taught what to do.
- Tue Jan 22, 2019 2:30 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: PH of Weak Acids and Bases
- Replies: 1
- Views: 157
PH of Weak Acids and Bases
I recall in lecture that a problem arises when calculating PH for a small amount of a weak acid that's smaller than 10^-7. I was wondering what I should do if this ever happens. Thanks!
- Tue Jan 22, 2019 2:26 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Conceptual questions
- Replies: 6
- Views: 497
Re: Conceptual questions
Maybe review autoprotolysis and ATP hydrolysis as well. These were 2 things included in lecture that may be important or asked about.
- Tue Jan 22, 2019 2:22 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Sig Figs of pKa
- Replies: 2
- Views: 5699
Re: Sig Figs of pKa
This applies to pKa and pKb as well because a log is being taken. If you try to use 10^-pKa/b, you will not get the concentration you initially had, so this rule remains.
- Wed Jan 16, 2019 7:32 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: partial pressure v concentration
- Replies: 4
- Views: 311
Re: partial pressure v concentration
I believe partial pressure can only be used for homogeneous gaseous reactions. Using Kp and Kc also depends of what information you've been given, like whether or not the problem lists things in M or atm.
- Tue Jan 15, 2019 11:18 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: ICE charts
- Replies: 3
- Views: 321
Re: ICE charts
I believe ICE charts only take concentrations. Like mol/L or partial pressures for gasses.
- Tue Jan 15, 2019 11:17 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Calculating Equilibrium values
- Replies: 2
- Views: 275
Re: Calculating Equilibrium values
If there are concentrations of both products and reactants, try to figure out Q and determine if the reaction needs to go to the left or the right. This is so you know whether or not to subtract x or add x to both sides. If only given one initial concentration on one side, assume x is subtracted fro...
- Mon Jan 14, 2019 2:21 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: 7th Edition 5H 3
- Replies: 2
- Views: 222
7th Edition 5H 3
I'm a bit confused as to how I can calculate K for the combination of 2 reactions on table 5G.2. This question asks for the value of K at 300 K for
2BrCl+H2 <-->Br2 +HCl. I don't believe this was taught in lecture, but it is on outline 1 so I'm looking for some tips.
Thanks!
2BrCl+H2 <-->Br2 +HCl. I don't believe this was taught in lecture, but it is on outline 1 so I'm looking for some tips.
Thanks!
- Mon Jan 07, 2019 7:59 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Topic 5G.9 7th Edition HW Problem
- Replies: 2
- Views: 194
Re: Topic 5G.9 7th Edition HW Problem
Both reactions occur under the same conditions, just with a different amount of O3 to begin with. More of this reactant will produce more of the product, but both reactions will have the SAME equilibrium constants. Because the concentration (or pressure) of O3 increases in the second experiment, the...
- Mon Jan 07, 2019 7:42 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Equilibrium vs Initial
- Replies: 2
- Views: 108
Re: Equilibrium vs Initial
I believe that equilibrium concentrations should be used when solving for K. In our lecture examples that's what we used, the concentrations of molecules at equilibrium.
- Mon Jan 07, 2019 7:40 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Video Module Post Assessment Question 12
- Replies: 3
- Views: 195
Video Module Post Assessment Question 12
For this question I put that "The forward reaction rate is the same as the reverse reaction rate" was false, but it was marked wrong.
I thought the reverse reaction rate was 1/Kc, so I'm confused as to why this was incorrect. Thanks!
I thought the reverse reaction rate was 1/Kc, so I'm confused as to why this was incorrect. Thanks!
- Sat Dec 08, 2018 12:02 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: H20 as ligand
- Replies: 1
- Views: 227
Re: H20 as ligand
It does have two lone pairs, but only one of them can attach to a center atom instead of a both. Because only oxygen attaches with one of its lone pairs, it's monodentate.
- Thu Dec 06, 2018 7:53 pm
- Forum: Lewis Structures
- Topic: Lewis structure of SO2
- Replies: 1
- Views: 323
Re: Lewis structure of SO2
Sulfur can have more than an octet, as added electrons can "fill" the 3d orbital. I think both structures are correct, but SO2 with 2 double bonds is more stable, as all atoms have a formal charge of 0.
- Wed Dec 05, 2018 6:52 pm
- Forum: Naming
- Topic: Water as a ligand
- Replies: 5
- Views: 623
Re: Water as a ligand
OH2 and H2O are the same! Oxygen has the lone pairs, so that's where the coordinate covalent bond forms in every situation. Some put O first to show Oxygen is the bonding site, however both OH2 and H2O are the same thing
- Tue Dec 04, 2018 12:32 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Naming on the Final
- Replies: 4
- Views: 557
Re: Naming on the Final
Typically more complex acids/bases will have names and formulas provided, but it's always nice to know more common ones and review the table in the book, just to stay sharp.
- Mon Dec 03, 2018 6:40 pm
- Forum: Naming
- Topic: 9C.3 7th edition
- Replies: 1
- Views: 186
Re: 9C.3 7th edition
The formulas don't have a charge because the combination of K3 and [Cr(CN)6] combine with no net charge
I don't think order matters much when writing in the brackets, as long as your anions are correct. However, order does matter when naming!
I don't think order matters much when writing in the brackets, as long as your anions are correct. However, order does matter when naming!
- Mon Nov 26, 2018 7:58 pm
- Forum: Polarisability of Anions, The Polarizing Power of Cations
- Topic: Polarizability
- Replies: 4
- Views: 767
Re: Polarizability
AlyssaBei_1B wrote:For polarizability, would the trend decrease across a period from right to left because the atoms are getting smaller from right to left?
Yes, polarizablity follows the same trends as atomic radii.
- Mon Nov 26, 2018 7:54 pm
- Forum: Polarisability of Anions, The Polarizing Power of Cations
- Topic: Polarizability
- Replies: 5
- Views: 430
Re: Polarizability
The trend in polarizability is similar to the trend of atomic radii. Decreases to the right and increases down the periodic table.
- Mon Nov 26, 2018 7:51 pm
- Forum: Polarisability of Anions, The Polarizing Power of Cations
- Topic: CN- v O2 stability
- Replies: 2
- Views: 408
Re: CN- v O2 stability
CN- has a triple bond, so it's bond is shorter and stronger than the double bond in O2
- Mon Nov 26, 2018 7:21 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Dipole Moment
- Replies: 3
- Views: 423
Re: Dipole Moment
The arrow points towards the more electronegative element. This element has a delta negative, as it's where the dipole moment goes.
- Fri Nov 23, 2018 4:48 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Drawing Structures on Test
- Replies: 11
- Views: 1001
Re: Drawing Structures on Test
Just know how to draw the lewis structure and name the shape based off of electron densities, bonds, and lone pairs. Wedges just help with visualization.
- Fri Nov 23, 2018 4:47 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Homework for week 9
- Replies: 11
- Views: 1192
Re: Homework for week 9
As long as you do the work and have it all together, you should be fine.
- Fri Nov 23, 2018 4:45 pm
- Forum: Hybridization
- Topic: when to use hybridization
- Replies: 4
- Views: 428
Re: when to use hybridization
Hybridization will most likely be asked. Just know how to mix your valence electrons to understand the concept itself.
- Fri Nov 23, 2018 4:42 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Polarity
- Replies: 7
- Views: 794
Re: Polarity
Dipole moments go towards the more electronegative element in a molecule. To determine polarity, consider the shape of the molecule itself. Take into account the arrows, where they're going, if they cancel out, or if they're different atoms. If everything cancels out, it's nonpolar, but if it's even...
- Wed Nov 14, 2018 6:00 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Electrons and VSEPR
- Replies: 4
- Views: 421
Re: Electrons and VSEPR
Lone Pairs do influence shape, they are still an area of electron concentration, and should be taken into consideration instead of being omitted.
- Tue Nov 13, 2018 6:38 pm
- Forum: Ionic & Covalent Bonds
- Topic: delta positive delta negative
- Replies: 15
- Views: 2346
Re: delta positive delta negative
Draw everything out first, then find the most electronegative atom (remember trends on the periodic table). This atom becomes delta negative, as it is an acceptor, and the other atom is delta positive.
- Tue Nov 13, 2018 6:36 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bond Angles
- Replies: 8
- Views: 1430
Re: Bond Angles
We weren't taught any set formula to calculate any bond angles. I believe the only way for us to really have an idea of what the angle may be is to memorize the shape of a molecule and what bond angles it yields.
- Mon Nov 05, 2018 1:52 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Alternative version of formula
- Replies: 7
- Views: 1003
Re: Alternative version of formula
Yes it works, use whatever formula you're most comfortable with, but understand what the formula presented means.
- Mon Nov 05, 2018 1:49 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Formal charges in charged molecules
- Replies: 5
- Views: 324
Re: Formal charges in charged molecules
Just carry out the process of drawing the lewis structure and finding formal charge. At the end of it all once it's balanced you'll be able to figure it out
- Mon Nov 05, 2018 1:46 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Calculator for Midterm
- Replies: 2
- Views: 366
Re: Calculator for Midterm
yes, as long as it isn't a graphing calculator
- Mon Oct 29, 2018 5:09 pm
- Forum: Einstein Equation
- Topic: E=hv [ENDORSED]
- Replies: 52
- Views: 18558
Re: E=hv [ENDORSED]
E represents the energy of the photon. h is Plancks's Constant (6.63*10^-34) and v is the calculated or measured frequency of a light source (typically UV or above for these equations)
- Mon Oct 29, 2018 5:05 pm
- Forum: Lewis Structures
- Topic: lewis structure
- Replies: 10
- Views: 1084
Re: lewis structure
Typically the atom with the lowest ionization energy ends up in the middle for lewis structure. Remember, ionization energy increases from going up and to the right of the periodic table.
- Mon Oct 29, 2018 5:00 pm
- Forum: Bond Lengths & Energies
- Topic: Bond Lengths
- Replies: 3
- Views: 379
Re: Bond Lengths
They're just the results that he found. There's no specific way we need to know to find these, they're just examples of bond lengths to put things into perspective.
- Wed Oct 24, 2018 7:00 pm
- Forum: Trends in The Periodic Table
- Topic: Seventh Edition 1F.11 C
- Replies: 1
- Views: 378
Seventh Edition 1F.11 C
I'm a little confused about part C of question 11. For the other answer choices in the same column, their electron affinities are equal. However, for oxygen and sulfur, sulfur has a higher affinity. Why is this so?
Thanks
Thanks
- Mon Oct 22, 2018 9:50 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Test 2
- Replies: 2
- Views: 344
Re: Test 2
Even if the test isn't concept heavy, it is useful to have a deep understanding of concepts. When you perform all your calculations, you can really understand what they mean and kind of predict what the answer will look like.
- Mon Oct 22, 2018 9:45 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Question 1E.7 B Seventh Edition
- Replies: 1
- Views: 125
Question 1E.7 B Seventh Edition
For part B of question 1E7, the electron configuration for nitrogen is considered to be excited. Is it because 2py is a down spin? I'm a little lost. Thanks!
- Mon Oct 22, 2018 9:32 pm
- Forum: Administrative Questions and Class Announcements
- Topic: DOWNLOAD SESSION WORKSHEETS HERE - Sundays 4-6pm (Karen) [ENDORSED]
- Replies: 135
- Views: 39575
Re: DOWNLOAD SESSION WORKSHEETS HERE - Sundays 4-6pm (Karen) [ENDORSED]
These really help me out a lot! Practice makes perfect, the more to do the better. Thanks!
- Tue Oct 16, 2018 6:40 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Orbitals problem 1E.11
- Replies: 2
- Views: 97
Re: Orbitals problem 1E.11
I would recommend waiting until we learn about orbitals in lecture. There's a lot of unnecessary stress involved trying to do problems that haven't been taught yet. For now just practice what we know, and when the time is right, practice orbitals!
- Tue Oct 16, 2018 6:35 pm
- Forum: *Particle in a Box
- Topic: Hw assignment?
- Replies: 7
- Views: 1300
Re: Hw assignment?
We're still in the quantum section. It's nice trying to get ahead and understanding things in advance,but I would recommend doing problems pertaining to what is currently being taught in class. This could save you some time and reduce stress!
- Tue Oct 16, 2018 6:32 pm
- Forum: DeBroglie Equation
- Topic: Mass of electrons
- Replies: 3
- Views: 354
Re: Mass of electrons
It will be given, but it's always helpful to know the mass of an electron is 9.11*10^-31 off the top of your head! It could save some time during tests so you wouldn't have to search for it!
- Fri Oct 12, 2018 11:01 am
- Forum: Einstein Equation
- Topic: Symbol for frequency
- Replies: 12
- Views: 2301
Re: Symbol for frequency
v is used in both lectures and the textbook, so it's probably the safest symbol to use.
- Tue Oct 09, 2018 6:04 pm
- Forum: Photoelectric Effect
- Topic: Vacuum
- Replies: 4
- Views: 335
Re: Vacuum
In the experiment, a detector is used. If it is not performed in a vacuum, then air molecules may get analyzed by the detector and interfere with the process. There is also the risk of air molecules interacting with the electrons in the experiment.
- Mon Oct 08, 2018 2:32 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Homework Question 1A.15, Seventh Edition Page 10
- Replies: 1
- Views: 163
Homework Question 1A.15, Seventh Edition Page 10
This questions observes a line of 102.6nm on the hydrogen spectrum. It then asks to determine the values of n for initial and final energy levels of the electron that lead to this line. Any tips for how to start?
Thanks!
Thanks!
- Mon Oct 08, 2018 2:12 pm
- Forum: Properties of Light
- Topic: Homework Question 1A.3 C, Seventh Edition Page 9
- Replies: 1
- Views: 99
Homework Question 1A.3 C, Seventh Edition Page 9
Question 1A.3 asks to clarify what happens when the frequency of electromagnetic radiation decreases. It's basically true of false with explanation. The part of the question that confused me was part C, which states: "The extent of the change in the electrical field at a given point decreases.&...
- Tue Oct 02, 2018 7:15 pm
- Forum: Balancing Chemical Reactions
- Topic: Problem L.35
- Replies: 5
- Views: 363
Re: Problem L.35
The solutions manual has Fe3Br8 listed. That's the only way it works out. I guess it's a typo in the Seventh edition :/
- Tue Oct 02, 2018 2:58 pm
- Forum: SI Units, Unit Conversions
- Topic: State Symbols
- Replies: 2
- Views: 305
State Symbols
Is it mandatory to include state symbols (s, l, aq, g) when writing out chemical equations? I was just wondering.
Thanks!
Thanks!
- Mon Oct 01, 2018 5:23 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Question E.9: Epsom Salts
- Replies: 2
- Views: 413
Question E.9: Epsom Salts
Any advice for writing formulas based off of a given name? In this case, how would one write out Magnesium Sulfate Heptahydrate?
Thanks!
Thanks!