Search found 102 matches

by Michelle Song 1I
Mon Mar 16, 2020 12:50 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: pH as Kw
Replies: 2
Views: 57

Re: pH as Kw

You squareroot Kw to find the concentration of hydronium ions and take the negative log of that.
by Michelle Song 1I
Sat Mar 14, 2020 10:42 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: Calculating K
Replies: 4
Views: 61

Re: Calculating K

kennedyp wrote:
Michelle Song 1I wrote:I don't think you can multiply both sides in k1 cause the left side of the Van't Hoff equation is ln(k2/k1) so you'd have to change that to ln(k2)-ln(k1) and add ln(k1) to both sides.

Oh okay my bad!! :(((
Don't worry about it! It's an easy mistake
by Michelle Song 1I
Sat Mar 14, 2020 5:57 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: Calculating K
Replies: 4
Views: 61

Re: Calculating K

I don't think you can multiply both sides in k1 cause the left side of the Van't Hoff equation is ln(k2/k1) so you'd have to change that to ln(k2)-ln(k1) and add ln(k1) to both sides.
by Michelle Song 1I
Sat Mar 14, 2020 5:28 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: 7C.7
Replies: 2
Views: 21

Re: 7C.7

Would the fact that two moles of NOBr are produced affect the rate law?
by Michelle Song 1I
Fri Mar 13, 2020 8:53 am
Forum: Zero Order Reactions
Topic: All reactants zero order?
Replies: 7
Views: 85

Re: All reactants zero order?

Yes, it could happen if they all depend on the presence of a catalyst.
by Michelle Song 1I
Fri Mar 13, 2020 8:49 am
Forum: Administrative Questions and Class Announcements
Topic: Test 2
Replies: 2
Views: 36

Test 2

If I want to talk to my TA about Test 2, could I do so over email?
by Michelle Song 1I
Wed Mar 11, 2020 12:43 pm
Forum: Administrative Questions and Class Announcements
Topic: Saying Thank You to Dr. Lavelle
Replies: 275
Views: 130231

Re: Saying Thank You to Dr. Lavelle

Dear Dr. Lavelle, Thank you so much for all the effort you've put into this class and in helping your students succeed. It was really helpful to have access to Chemistry Community and all the review sessions and I really appreciate the amount of work it takes to organize all of that and how dedicate...
by Michelle Song 1I
Mon Mar 09, 2020 12:08 am
Forum: Method of Initial Rates (To Determine n and k)
Topic: differential rate law to integrated rate law
Replies: 3
Views: 22

Re: differential rate law to integrated rate law

The integrated rate law equations allow you to find the concentrations of reactants in regards to time and vice versa.
by Michelle Song 1I
Sun Mar 08, 2020 11:59 pm
Forum: Method of Initial Rates (To Determine n and k)
Topic: units of T
Replies: 11
Views: 366

Re: units of T

Unless the question states otherwise, it's seconds.
by Michelle Song 1I
Sun Mar 08, 2020 11:37 pm
Forum: General Rate Laws
Topic: First vs Second vs Zero Order
Replies: 7
Views: 47

Re: First vs Second vs Zero Order

The order of a reaction tells you how the rate of that reaction changes in response to changes in the reactants' concentrations.
by Michelle Song 1I
Sun Mar 08, 2020 11:36 pm
Forum: General Rate Laws
Topic: Pseudo rate law
Replies: 3
Views: 24

Re: Pseudo rate law

I think a pseudo rate law helps you find the order of an individual reactant in a reaction. You can use it when the concentrations of the other reactions are so large that a decrease in concentration doesn't really affect them, allowing you to focus on a single reactant.
by Michelle Song 1I
Sun Mar 08, 2020 11:10 pm
Forum: Kinetics vs. Thermodynamics Controlling a Reaction
Topic: units
Replies: 11
Views: 88

Re: units

It's moles per liter per time in sec. However, the units for k will change depending on what order of reaction it is.
by Michelle Song 1I
Sun Mar 08, 2020 11:09 pm
Forum: Kinetics vs. Thermodynamics Controlling a Reaction
Topic: order of reactions
Replies: 7
Views: 88

Re: order of reactions

It tells you how (or whether) changes in the concentrations of products will affect the rate of reaction.
by Michelle Song 1I
Sun Mar 08, 2020 11:08 pm
Forum: Kinetics vs. Thermodynamics Controlling a Reaction
Topic: intermediate
Replies: 22
Views: 565

Re: intermediate

An intermediate was formed (and then used up) by the reaction, so it doesn't show up in the rate law.
by Michelle Song 1I
Sun Mar 08, 2020 11:07 pm
Forum: Kinetics vs. Thermodynamics Controlling a Reaction
Topic: Problems
Replies: 6
Views: 43

Re: Problems

Consider both Kinetics and Thermodynamics?
by Michelle Song 1I
Mon Mar 02, 2020 5:47 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Water in Cell Diagrams
Replies: 2
Views: 32

Water in Cell Diagrams

How come the cell diagram in 6L.3 part d leaves out water? Is there ever a time we should include water, or any liquid, in a cell diagram?
by Michelle Song 1I
Mon Mar 02, 2020 5:41 pm
Forum: Student Social/Study Group
Topic: Today's Workshop
Replies: 2
Views: 60

Today's Workshop

Couldn't make it to Lyndon's workshop, is anyone willing to share the problems? Or anything he said that would be good to know?
by Michelle Song 1I
Mon Feb 24, 2020 5:38 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Platinum
Replies: 5
Views: 56

Re: Platinum

If you need to write a cell diagram and a half-reaction doesn't have a solid, you can use platinum.
by Michelle Song 1I
Mon Feb 24, 2020 5:36 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: No Conducting Solids
Replies: 1
Views: 36

Re: No Conducting Solids

I believe Dr. Lavelle may have been referring to the Fe half-reaction, in which both the product and reactant are in solution.
by Michelle Song 1I
Mon Feb 24, 2020 5:34 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Oxidation versus reduction
Replies: 9
Views: 65

Re: Oxidation versus reduction

Yeah you can pretty much assume anion is left and cathode is right unless the question is worded in a way that implies differently.
by Michelle Song 1I
Mon Feb 24, 2020 5:24 am
Forum: Balancing Redox Reactions
Topic: Determining direction of flow
Replies: 15
Views: 121

Re: Determining direction of flow

The electrons flow from the anode to the cathode.
by Michelle Song 1I
Mon Feb 24, 2020 5:23 am
Forum: Balancing Redox Reactions
Topic: Balancing Redox Reactions
Replies: 7
Views: 58

Re: Balancing Redox Reactions

J Medina 2I wrote:What are basic conditions?
Conditions where the pH is above 7
by Michelle Song 1I
Sun Feb 23, 2020 1:36 am
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: n in -nFE
Replies: 12
Views: 88

Re: n in -nFE

n is the number of moles of electrons, which you can find after balancing the half reactions.
by Michelle Song 1I
Sun Feb 23, 2020 1:35 am
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: 6L.1
Replies: 4
Views: 37

Re: 6L.1

They're the same number, just different sig figs (which shouldn't matter since it's a constant)
by Michelle Song 1I
Sun Feb 23, 2020 1:33 am
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Voltage Energies
Replies: 3
Views: 35

Re: Voltage Energies

The equation for overall cell potential already takes into account that the values for standard reduction potentials that are given are all positive, which is why you don't have to change the sign before inputting it into the equation.
by Michelle Song 1I
Sun Feb 23, 2020 1:30 am
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: n in -nFE
Replies: 14
Views: 185

Re: n in -nFE

It's the number of electrons transferred, which you can find in the half reactions (after balancing them).
by Michelle Song 1I
Sun Feb 23, 2020 1:29 am
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: work and cell potential
Replies: 4
Views: 45

Re: work and cell potential

Adding on to the people above me, Faraday's constant is the charge on a mole of electrons, so the expression nFE is just the total amount of charge multiplied with the average amount of Joules per charge, which gives work.
by Michelle Song 1I
Sat Feb 22, 2020 2:34 am
Forum: Balancing Redox Reactions
Topic: Redox in Acid/ Basic Solutions
Replies: 8
Views: 59

Re: Redox in Acid/ Basic Solutions

For acidic reactions you add H+ to balance out the hydrogen atoms and in basic reactions you add OH- to then cancel out the H+ ions.
by Michelle Song 1I
Sat Feb 22, 2020 2:30 am
Forum: Balancing Redox Reactions
Topic: balancing half reactions in a basic solution
Replies: 7
Views: 58

Re: balancing half reactions in a basic solution

Yes, kinda like in math, whatever you do to one side you should do to both.
by Michelle Song 1I
Sat Feb 22, 2020 2:29 am
Forum: Balancing Redox Reactions
Topic: HW 6K.5 a
Replies: 1
Views: 43

Re: HW 6K.5 a

My guess for some of your questions would be since Br is being oxidized, you can assume that O3 is reduced, which kinda makes sense considering it loses an oxygen.
by Michelle Song 1I
Sat Feb 22, 2020 2:24 am
Forum: Balancing Redox Reactions
Topic: Charge of oxygen
Replies: 15
Views: 119

Re: Charge of oxygen

Shouldn't the oxidation state of oxygen in O2 be zero?
by Michelle Song 1I
Sat Feb 22, 2020 2:20 am
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Adding Inert Gas
Replies: 20
Views: 256

Re: Adding Inert Gas

Adding an inert gas will not cause the reaction to shift in either direction.
by Michelle Song 1I
Tue Feb 04, 2020 6:07 pm
Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
Topic: R constants
Replies: 21
Views: 599

Re: R constants

The way you determine is by looking at the units you have.
by Michelle Song 1I
Tue Feb 04, 2020 6:05 pm
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: chen discussion [ENDORSED]
Replies: 5
Views: 67

Re: chen discussion [ENDORSED]

Do you mind posting the entire question?
by Michelle Song 1I
Tue Feb 04, 2020 6:00 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Work done BY vs work done ON
Replies: 9
Views: 76

Re: Work done BY vs work done ON

Work done by the system is associated with an increase in volume (and, therefore, has a negative sign) and work done onto the system is associated with a decrease in volume (resulting in a positive sign).
by Michelle Song 1I
Tue Feb 04, 2020 3:38 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: q and w
Replies: 10
Views: 91

Re: q and w

q would be positive if heat is being added to the system and negative if heat is being removed. w would be positive if work is done by the system and negative if work is done on the system. what is an example of work being done on or to the system? An example of work being done on a system would be...
by Michelle Song 1I
Tue Feb 04, 2020 3:03 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Differences between systems
Replies: 3
Views: 32

Re: Differences between systems

In a closed system, energy is exchanged with its surroundings, but matter isn't, such as a sealed beaker of water. In an isolated system, nothing is exchanged with the surroundings, like the combustion of glucose in a bomb calorimeter.
by Michelle Song 1I
Mon Feb 03, 2020 6:24 pm
Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
Topic: ∆U
Replies: 8
Views: 67

Re: ∆U

It is the final internal energy minus the initial internal energy of the system.
by Michelle Song 1I
Mon Feb 03, 2020 6:22 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Car Engine
Replies: 4
Views: 52

Re: Car Engine

Because it exchanges energy and mass with its surroundings.
by Michelle Song 1I
Fri Jan 24, 2020 6:48 pm
Forum: Administrative Questions and Class Announcements
Topic: First Quarter Final
Replies: 1
Views: 39

First Quarter Final

Hey, I forgot that we could pick up our finals this week and I was wondering if I could pick mine up next week?
by Michelle Song 1I
Thu Jan 16, 2020 10:41 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 6D.15 PART B
Replies: 5
Views: 54

Re: 6D.15 PART B

Sara Richmond 2K wrote:Yes, I am sure that I am looking at the right solution manual question. The answer to part A is actually 5. I have included a screen shot of my work to show how to get 5 for part A.
Oh whoops, I assumed that NH4Cl dissociated completely, sorry.
by Michelle Song 1I
Thu Jan 16, 2020 10:38 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 6D.13
Replies: 4
Views: 41

Re: 6D.13

You should know that strong acids dissociate completely, which is why they don't have Ka constants, and thus result in solutions with higher H+ concentrations. Thus, if you are comparing two strong acid solutions, you can expect the one with a higher molarity to be more acidic. So is there a chart ...
by Michelle Song 1I
Thu Jan 16, 2020 4:51 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: percentage reacted
Replies: 3
Views: 55

Re: percentage reacted

Equilibrium constants are calculated using concentrations (or partial pressures, depending), so you could find the number of moles of reactants and product at equilibrium for this reaction, but you would have to convert them to concentrations in order to find the equilibrium constant.
by Michelle Song 1I
Thu Jan 16, 2020 4:33 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Q and K
Replies: 4
Views: 36

Re: Q and K

If Q is less than K that means the ratio of products to reactants is too low and the reaction will shift towards the products. If it is more than K then the reaction will shift towards the reactants.
by Michelle Song 1I
Thu Jan 16, 2020 4:29 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Difference Kw Value
Replies: 3
Views: 46

Re: Difference Kw Value

I believe that anytime the the concentration of H30+ = concentration OH- is considered neutral even if the ph isn't 7, which is neutral for water at room temperature. If kw changes because of a change in temperature then we should expect the ph scale and what is acidic, neutral, and basic should al...
by Michelle Song 1I
Thu Jan 16, 2020 4:25 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 6D.15 PART B
Replies: 5
Views: 54

Re: 6D.15 PART B

I don't have the solutions manual in front of me so I can't check, but are you sure you're looking at the right solution? The solutions manual appears to be saying that the answer for part a is 5.00, and that's not the pH of 0.19 M NH4Cl.
by Michelle Song 1I
Thu Jan 16, 2020 4:11 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 6D.13
Replies: 4
Views: 41

Re: 6D.13

You should know that strong acids dissociate completely, which is why they don't have Ka constants, and thus result in solutions with higher H+ concentrations. Thus, if you are comparing two strong acid solutions, you can expect the one with a higher molarity to be more acidic.
by Michelle Song 1I
Thu Jan 16, 2020 4:08 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Inert Gas
Replies: 7
Views: 51

Re: Inert Gas

Noble gases like Neon and Argon are inert.
by Michelle Song 1I
Thu Jan 16, 2020 4:07 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Change in pressure effect on reactions
Replies: 3
Views: 23

Re: Change in pressure effect on reactions

It depends on how you change pressure. If you add pressure by decreasing the volume of the system, then you're also increasing the concentrations of the reactants and products, thus making the reaction shift to whatever side has the least number of moles (and vice versa if you decrease pressure by i...
by Michelle Song 1I
Thu Jan 16, 2020 4:02 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Difference Kw Value
Replies: 3
Views: 46

Difference Kw Value

In the cases where Kw is a different value than 1.0 x 10^-14, assuming that [OH] still equals [H3O] and vice versa, wouldn't that mean that both the pH and pOH of the system are either lower or higher than 7? For example, if the Kw was higher than 1.0 x 10^-14, since [OH] = [H3O], wouldn't both of t...
by Michelle Song 1I
Thu Jan 16, 2020 2:40 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 5.35 part b
Replies: 4
Views: 39

Re: 5.35 part b

Renee Grange 1I wrote:The divide by 100 in order to convert pKa to bar. 1 pKa = .01 bar.
Thank you! Did he mention this in lecture?
by Michelle Song 1I
Thu Jan 16, 2020 2:40 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 5.35 part b
Replies: 4
Views: 39

Re: 5.35 part b

VPatankar_3L wrote:Yes I think you should always convert from Pa to atm or bar before you continue with calculations.
Ah okay, thank you! Did Dr. Lavelle mention this in lecture?
by Michelle Song 1I
Thu Jan 16, 2020 11:46 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 5.35 part b
Replies: 4
Views: 39

5.35 part b

When calculating the equilibrium constant, the solution divides each of the values given on the plot (which are in kPa) by 100. Is this to convert it from kPa to atm? And if so, does that mean gas equilibrium constants can only be calculated using partial pressures in atm?
by Michelle Song 1I
Thu Jan 16, 2020 11:39 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 6A19 part c
Replies: 5
Views: 54

Re: 6A19 part c

I was wondering about this too. The book gives 3.2 x 10^-12 as the answer because it multiplies 3.1 by 10^-3, which I think implies that it has something to do with units. However, the units of 3.1 are mol*L^-1, which are the same units the values in the other parts had and those values weren't mult...
by Michelle Song 1I
Tue Nov 26, 2019 4:20 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: brackets
Replies: 13
Views: 91

Re: brackets

Whatever is inside the brackets is part of the coordination sphere.
by Michelle Song 1I
Tue Nov 26, 2019 4:17 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Cis vs Trans
Replies: 21
Views: 384

Re: Cis vs Trans

cis molecules have the same groups on one side and trans molecules have them on opposing sides.
by Michelle Song 1I
Tue Nov 26, 2019 4:15 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Oxidation Number vs. Coordination Number
Replies: 8
Views: 81

Re: Oxidation Number vs. Coordination Number

DMuth_1J wrote:if coordination number is the number of bonds, then what is valence?


Valence is the number of electrons an atom/ion has in their outer shell
by Michelle Song 1I
Tue Nov 26, 2019 4:10 pm
Forum: Conjugate Acids & Bases
Topic: Acids and Bases
Replies: 10
Views: 82

Re: Acids and Bases

I remember Dr. Lavelle still used the equilibrium arrows for a reaction with a strong acid in water though. I can't remember what he said when he explained why.
by Michelle Song 1I
Tue Nov 26, 2019 4:08 pm
Forum: Conjugate Acids & Bases
Topic: Cojugate Acids and Bases
Replies: 10
Views: 447

Re: Cojugate Acids and Bases

The one with the hydrogen ion is the acid and the one without is the base
by Michelle Song 1I
Tue Nov 26, 2019 4:05 pm
Forum: Biological Examples
Topic: Cisplatin
Replies: 12
Views: 136

Re: Cisplatin

ATingin_3I wrote:
ashwathinair wrote:You should know cisplatin has a different structure than the trans version of the molecule because of sigma and pi bonds and the lewis structures of each.


so what would transplatin be used for?


Nothing in particular
by Michelle Song 1I
Tue Nov 26, 2019 4:03 pm
Forum: Naming
Topic: polydentate?
Replies: 7
Views: 70

Re: polydentate?

What exactly does the suffix "-dentate" refer to? "Dentate" kind of means "bite", which refers to the bonds that form between the ligand and the central ion (a bond is similar to the ligand "biting" onto the ion). So a polydentate is a "ligand" that...
by Michelle Song 1I
Tue Nov 26, 2019 3:58 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Why are inorganic acids stronger?
Replies: 8
Views: 92

Re: Why are inorganic acids stronger?

Their bonds tend to be more polar, making them more easily deprotonated.
by Michelle Song 1I
Tue Nov 26, 2019 3:50 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Structure of H2SO4
Replies: 2
Views: 35

Re: Structure of H2SO4

Once it's in water, the hydrogen ions will dissociate.
by Michelle Song 1I
Sun Nov 24, 2019 7:42 pm
Forum: Biological Examples
Topic: Cisplatin
Replies: 12
Views: 136

Re: Cisplatin

Cisplatin is used in a certain kind of chemotherapy. It stops DNA from replicating by binding onto the guanine residues. It can only bind when the DNA is replicating, which is usually DNA in cancer cells. However, it can also affect healthy cells with replicating DNA.
by Michelle Song 1I
Sun Nov 24, 2019 7:39 pm
Forum: Naming
Topic: atoms outside of the coordination complex
Replies: 2
Views: 31

Re: atoms outside of the coordination complex

Would you mind posting the homework question and solution you're talking about?
by Michelle Song 1I
Sun Nov 24, 2019 7:37 pm
Forum: Naming
Topic: Week 9 and Week 10 HW?
Replies: 21
Views: 216

Re: Week 9 and Week 10 HW?

Probably, so long as you label them
by Michelle Song 1I
Sun Nov 24, 2019 6:47 pm
Forum: Naming
Topic: Importance
Replies: 1
Views: 31

Re: Importance

Probably about as important as knowing how to name a compound, considering it's pretty much the same information
by Michelle Song 1I
Sun Nov 24, 2019 6:46 pm
Forum: Naming
Topic: polydentate?
Replies: 7
Views: 70

Re: polydentate?

It bonds to the central ion in more than one place
by Michelle Song 1I
Sun Nov 24, 2019 6:45 pm
Forum: Naming
Topic: Order in Naming
Replies: 12
Views: 108

Re: Order in Naming

I agree, the names of the ligands still have to be in alphabetical order in the formula
by Michelle Song 1I
Sun Nov 24, 2019 6:42 pm
Forum: Naming
Topic: 9C.1
Replies: 3
Views: 44

Re: 9C.1

Start with naming the ligands
by Michelle Song 1I
Sun Nov 17, 2019 9:54 pm
Forum: Formal Charge and Oxidation Numbers
Topic: Calculating formal charge
Replies: 8
Views: 160

Re: Calculating formal charge

It doesn't matter which one you calculate first.
by Michelle Song 1I
Tue Nov 12, 2019 5:48 am
Forum: Polarisability of Anions, The Polarizing Power of Cations
Topic: polarizability and polarizing power
Replies: 4
Views: 48

Re: polarizability and polarizing power

The smaller and more highly charged a cation is the more polarizing power it has.
by Michelle Song 1I
Tue Nov 12, 2019 5:45 am
Forum: Coordinate Covalent Bonds
Topic: Determining bonds
Replies: 4
Views: 144

Re: Determining bonds

A general rule to remember is that if the electronegativity difference is >2.0, the bond is ionic and if it's 1.5> and >.5 then it's polar covalent. If it's <.5 then it's nonpolar covalent.
by Michelle Song 1I
Tue Nov 12, 2019 5:41 am
Forum: Octet Exceptions
Topic: Octet exception
Replies: 13
Views: 385

Re: Octet exception

Boron and Aluminum are also exceptions in that they can form only 3 bonds.
by Michelle Song 1I
Tue Nov 12, 2019 5:39 am
Forum: Lewis Structures
Topic: Center of a Lewis Structure
Replies: 7
Views: 78

Re: Center of a Lewis Structure

I go with the least electronegative atom, which tends to be the atom with the lowest ionization energy except in the case of nitrogen and oxygen, in which oxygen has a lower ionization energy but is more electronegative (in this case, I believe nitrogen is used as the central atom).
by Michelle Song 1I
Sun Nov 10, 2019 3:07 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: How to Draw Dipole Arrows
Replies: 8
Views: 115

Re: How to Draw Dipole Arrows

I'm pretty sure δ is used to indicate the charge on the atoms and the dipole arrows are drawn going from the positive to negatively charged atoms.
by Michelle Song 1I
Mon Nov 04, 2019 12:57 am
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Drawing Orbitals
Replies: 3
Views: 123

Re: Drawing Orbitals

You probably only have to know the basics of the shapes of the orbitals, like how s-orbitals are a sphere, p-orbitals are like dumbbells, and so on. Also the number of nodes for each type of orbital. I'm pretty sure we don't need to know about f-orbitals though.
by Michelle Song 1I
Mon Nov 04, 2019 12:54 am
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Electron Configurations
Replies: 2
Views: 122

Re: Electron Configurations

Yes, in the review session I went to today, the TA said we didn't have to specify px, py, pz
by Michelle Song 1I
Sun Nov 03, 2019 11:17 pm
Forum: Quantum Numbers and The H-Atom
Topic: Formal names for each letter
Replies: 5
Views: 159

Re: Formal names for each letter

To add on to previous responses, mx is the spin of the electron and can be either positive or negative 1/2
by Michelle Song 1I
Sun Nov 03, 2019 11:06 pm
Forum: Trends in The Periodic Table
Topic: Dino Nugget Mini review
Replies: 3
Views: 90

Re: Dino Nugget Mini review

I assume it is Li+ since I think for cations, they have more polarizing power with higher charge and smaller radius.
by Michelle Song 1I
Sun Nov 03, 2019 11:04 pm
Forum: Properties of Light
Topic: Finding Frequency
Replies: 3
Views: 82

Finding Frequency

How would you find the frequency of a particle that is not a photon?
by Michelle Song 1I
Sun Oct 27, 2019 11:16 pm
Forum: Trends in The Periodic Table
Topic: 1F.5a
Replies: 4
Views: 47

Re: 1F.5a

Because Na also has a smaller effective nuclear charge than Al, and they have the same number of "shielding electrons".
by Michelle Song 1I
Sun Oct 27, 2019 11:10 pm
Forum: Resonance Structures
Topic: Kekule Structure
Replies: 2
Views: 35

Re: Kekule Structure

It also doesn't include lone pairs of electrons.
by Michelle Song 1I
Sun Oct 27, 2019 11:06 pm
Forum: Ionic & Covalent Bonds
Topic: Covalent bonds and cations
Replies: 3
Views: 44

Re: Covalent bonds and cations

A high ionization energy means that it is difficult for it to lose electrons, thus, it is unlikely that a nonmetal will gain a positive charge.
by Michelle Song 1I
Sun Oct 27, 2019 11:05 pm
Forum: Ionic & Covalent Bonds
Topic: Ionic Bonds confusion
Replies: 7
Views: 96

Re: Ionic Bonds confusion

Metals tend to form cations and nonmetals tend to form anions, meaning metals will tend to donate electrons to nonmetals.
by Michelle Song 1I
Sun Oct 27, 2019 10:58 pm
Forum: Ionic & Covalent Bonds
Topic: 2A. 13 Question
Replies: 5
Views: 68

Re: 2A. 13 Question

Adding on to what the person above me said, it's also important to remember that transition metals in the d-block will lose electrons in the s-orbital first.
by Michelle Song 1I
Sun Oct 20, 2019 10:22 pm
Forum: Photoelectric Effect
Topic: Clarification on Photoelectric Effect
Replies: 3
Views: 66

Re: Clarification on Photoelectric Effect

Increasing the energy of the photon (or decreasing its wavelength) is needed to eject an electron. Increasing the intensity of light simply increases the number of photons and, if the energy in one photon isn't enough, it doesn't matter how many there are since none of them will launch an electron (...
by Michelle Song 1I
Sun Oct 20, 2019 10:18 pm
Forum: Properties of Electrons
Topic: Absorption and Emission Spectra of Electrons
Replies: 1
Views: 58

Re: Absorption and Emission Spectra of Electrons

The Lyman series is a series of transitions that result in emission lines and is defined by the fact that the nf is 1. I haven't seen it used to describe wavelength absorption, but if it is I would assume that it applies to transitions where the ni is 1.
by Michelle Song 1I
Sun Oct 20, 2019 10:10 pm
Forum: Properties of Light
Topic: 1F.19
Replies: 5
Views: 61

Re: 1F.19

This is kinda a simple way of thinking about it but atoms want to have a full electron shell and since s-block metals only need to lose 1-2 valence electrons in order to have a full shell they really want to lose them, which is why they react more easily.
by Michelle Song 1I
Sun Oct 20, 2019 10:07 pm
Forum: Properties of Light
Topic: Wave Properties of Sound
Replies: 4
Views: 70

Re: Wave Properties of Sound

Yes, constructive and destructive interference apply to sound (which is a longitudinal wave), you can use tuning forks to demonstrate this (it's fun to play around with them).
by Michelle Song 1I
Sun Oct 20, 2019 10:05 pm
Forum: Properties of Light
Topic: Midterm Exam
Replies: 21
Views: 255

Re: Midterm Exam

Do we know when the midterm is yet?
by Michelle Song 1I
Sun Oct 13, 2019 4:44 pm
Forum: Properties of Light
Topic: Wave-Particle Behavior
Replies: 4
Views: 76

Re: Wave-Particle Behavior

The photoelectric experiments support the particle behavior view, Young's double slit experiment (or any experiments that involve the diffraction of light) supports the wave behavior view (although I remember something about how light will act differently when its being observed). Someone above alre...
by Michelle Song 1I
Sun Oct 13, 2019 4:38 pm
Forum: Properties of Light
Topic: Photoelectric vs. Atomic spectra
Replies: 4
Views: 44

Re: Photoelectric vs. Atomic spectra

One difference is that the photoelectric experiments involve completely removing the electron from the atom and measuring the properties of the removed electron, whereas atomic spectroscopy only involves the transition of an electron in between the energy levels of an atom. The electron can be excit...
by Michelle Song 1I
Sun Oct 13, 2019 4:33 pm
Forum: Properties of Light
Topic: type of light during p.e. experiment
Replies: 2
Views: 35

Re: type of light during p.e. experiment

It does seem that visible light is most commonly used, but any type of light can be used to cause the photoelectric effect so long as its wavelength is shorter than 683 nm.
by Michelle Song 1I
Sun Oct 13, 2019 4:29 pm
Forum: Properties of Light
Topic: Intensity of light
Replies: 2
Views: 35

Re: Intensity of light

The above reply is true if light acts simply as a wave, as the photoelectric experiment has demonstrated, light also acts a particle, in which case increasing its intensity would be increasing the number of photons.
by Michelle Song 1I
Sun Oct 13, 2019 4:27 pm
Forum: Properties of Light
Topic: HW Question 1A.11
Replies: 2
Views: 55

Re: HW Question 1A.11

Each series contains the transitions of an electron going from a higher energy to a specific lower energy level. For the Lyman series, the lower energy level is n = 1, for Balmer, the lower energy level is n = 2 and so on. So essentially, what is common to the lines within a series is that they end ...
by Michelle Song 1I
Sat Oct 05, 2019 1:49 am
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Question L7
Replies: 3
Views: 94

Re: Question L7

Amir Bayat wrote:Alright, that is what I believed it to be.

Thank you.

No problem, glad I could help.
by Michelle Song 1I
Thu Oct 03, 2019 4:33 pm
Forum: SI Units, Unit Conversions
Topic: Sig Figs: follow the book or follow Sig Fig rules?
Replies: 3
Views: 100

Re: Sig Figs: follow the book or follow Sig Fig rules?

My TA said that most TAs won't care about sig figs when grading homework, and I would personally go with following the sig fig rules because then, if you actually do get points taken off, you have a good defense for your answer as the established rules should hold precedence over what the solutions ...
by Michelle Song 1I
Thu Oct 03, 2019 4:26 pm
Forum: Balancing Chemical Reactions
Topic: H.25 Question
Replies: 3
Views: 96

Re: H.25 Question

I believe so, I'd recommend looking up homonuclear molecules to learn more.
by Michelle Song 1I
Thu Oct 03, 2019 1:25 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Question L7
Replies: 3
Views: 94

Re: Question L7

The mass of oxygen will be the same whether you convert from moles of O2 or O as the number of moles of O is twice the number of moles of O2 and the molar mass of O is half the molar mass of O2.

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