Search found 72 matches

by Lisa Werner 2F
Sun Mar 17, 2019 12:42 am
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: adiabatic vs isothermal
Replies: 2
Views: 196

adiabatic vs isothermal

what is the difference between adiabatic and isothermal?
by Lisa Werner 2F
Sat Mar 16, 2019 11:23 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: Final
Replies: 5
Views: 265

Re: Final

i have heard from past students that there is also a large portion based on thermodynamics.
by Lisa Werner 2F
Sat Mar 16, 2019 11:22 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: atm to torr
Replies: 3
Views: 203

atm to torr

what is the conversion from atm to torr?
by Lisa Werner 2F
Sat Mar 16, 2019 11:18 pm
Forum: Kinetics vs. Thermodynamics Controlling a Reaction
Topic: A in the arrhenius equation
Replies: 2
Views: 329

A in the arrhenius equation

conceptually, what does A mean in the arrhenius equation mean?
by Lisa Werner 2F
Sat Mar 16, 2019 11:15 pm
Forum: First Order Reactions
Topic: Rate Law
Replies: 2
Views: 189

Re: Rate Law

lyndon said that we probably wouldn't have to know how to derive equations, but if it's on the syllabus it may appear on the test
by Lisa Werner 2F
Sat Mar 16, 2019 11:13 pm
Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
Topic: adiabatic systems
Replies: 7
Views: 245

Re: adiabatic systems

it means that q=0, so delta=w. it will usually be specified in the problem.
by Lisa Werner 2F
Sat Mar 16, 2019 11:10 pm
Forum: Administrative Questions and Class Announcements
Topic: LYNDON'S PORK RAMEN REVIEW
Replies: 37
Views: 2680

Re: LYNDON'S PORK RAMEN REVIEW

thank you lyndon !!!
by Lisa Werner 2F
Sat Mar 16, 2019 11:09 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Porous Disk vs Salt Bridge
Replies: 3
Views: 203

Re: Porous Disk vs Salt Bridge

yes, a porous disc is notated by a single line
by Lisa Werner 2F
Sat Mar 16, 2019 11:08 pm
Forum: Administrative Questions and Class Announcements
Topic: DOWNLOAD SESSION WORKSHEETS HERE - Sun 7-9PM (Karen)
Replies: 179
Views: 7811

Re: DOWNLOAD SESSION WORKSHEETS HERE - Sun 7-9PM (Karen)

thank you so much karen! these worksheets were so helpful!
by Lisa Werner 2F
Sat Mar 16, 2019 11:07 pm
Forum: Administrative Questions and Class Announcements
Topic: DOWNLOAD SESSION WORKSHEETS HERE - Sun 7-9PM (Karen)
Replies: 179
Views: 7811

Re: DOWNLOAD SESSION WORKSHEETS HERE - Sun 7-9PM (Karen)

in worksheet 5 problem 6, how do we know that work is 0?
by Lisa Werner 2F
Sat Mar 16, 2019 10:33 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Steady State Approximation
Replies: 3
Views: 201

Re: Steady State Approximation

i think dr. lavelle said that he wouldn't make us do it because the math is too complicated.
by Lisa Werner 2F
Sat Mar 16, 2019 10:32 pm
Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
Topic: when is w=0 and when is q=0?
Replies: 1
Views: 196

when is w=0 and when is q=0?

when is w=0 and when is q=0? what are the key words that indicate these two conditions?
by Lisa Werner 2F
Sat Mar 16, 2019 10:31 pm
Forum: Van't Hoff Equation
Topic: neutral pH not 7?
Replies: 6
Views: 267

Re: neutral pH not 7?

at different temperatures, ph 7 is not always neutral.
by Lisa Werner 2F
Thu Mar 14, 2019 12:58 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: deltaU=0
Replies: 1
Views: 169

deltaU=0

what are scenarios/conditions where deltaU=0?
by Lisa Werner 2F
Sun Mar 10, 2019 6:12 pm
Forum: Second Order Reactions
Topic: Final
Replies: 30
Views: 488

Re: Final

it will be cumulative, but watch out for topics that have not yet been tested in class (kinetics)
by Lisa Werner 2F
Sun Mar 10, 2019 6:08 pm
Forum: First Order Reactions
Topic: graph
Replies: 3
Views: 55

Re: graph

the actual concentration of A in first order reactions is exponentially decaying; however, we plot the y axis using ln, which gives us a linear graph with a slope
by Lisa Werner 2F
Sun Mar 10, 2019 6:05 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Molecularity
Replies: 3
Views: 63

Re: Molecularity

molecularity is based upon the number of types of reactant molecules in a reaction
by Lisa Werner 2F
Sun Mar 10, 2019 6:00 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Orders
Replies: 2
Views: 52

Re: Orders

the order of a reaction is equal to the sum of the powers of each term in the rate law. for example, if you had rate=[A]^2[B]^1[C]^3 then 2+1+3=6 so the order of the reaction described by that particular rate law would be 6
by Lisa Werner 2F
Sun Mar 10, 2019 5:56 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Calculating E naught
Replies: 5
Views: 75

Re: Calculating E naught

when you find the two half reactions in the from of reductions from an original equation, whichever one has the reactants and product on the same side as the original is the cathode and the one where the reactants and products are flipped is the anode.
by Lisa Werner 2F
Sun Mar 10, 2019 5:53 pm
Forum: Administrative Questions and Class Announcements
Topic: Midterm average
Replies: 5
Views: 141

Re: Midterm average

Dr. Lavelle announced in lecture that the midterm average was an 80%.
by Lisa Werner 2F
Sun Mar 10, 2019 5:52 pm
Forum: Student Social/Study Group
Topic: Final
Replies: 24
Views: 751

Re: Final

when lyndon posts his review worksheet, it will probably be announced in lecture.
by Lisa Werner 2F
Sun Mar 10, 2019 5:47 pm
Forum: General Rate Laws
Topic: writing rate laws
Replies: 4
Views: 65

Re: writing rate laws

from my understanding: they both refer to the same equation; however, "the rate of consumption of ____" could change the sign. for example, if it is the rate of consumption of a reactant then it will be positive, but if it is the rate of consumption of a product then it will be negative.
by Lisa Werner 2F
Sun Mar 10, 2019 5:43 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Equation I've never seen before?
Replies: 3
Views: 72

Re: Equation I've never seen before?

it is just a specific case of the gas law equation pv=nrt
by Lisa Werner 2F
Wed Feb 13, 2019 12:05 am
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: 3/2R vs 5/2R
Replies: 8
Views: 175

3/2R vs 5/2R

how can we tell when to use 3/2R and 5/2R as C?
by Lisa Werner 2F
Tue Feb 12, 2019 4:22 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: deltaU=0
Replies: 3
Views: 76

Re: deltaU=0

delta u is 0 when q=-w
by Lisa Werner 2F
Tue Feb 12, 2019 4:18 pm
Forum: Administrative Questions and Class Announcements
Topic: Midterm
Replies: 6
Views: 176

Re: Midterm

I believe everything in that lecture could be in it, except for the Gibbs free energy.
by Lisa Werner 2F
Tue Feb 12, 2019 4:17 pm
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: temp units
Replies: 3
Views: 65

Re: temp units

You should do the calculations with kelvin.
by Lisa Werner 2F
Wed Feb 06, 2019 5:39 pm
Forum: Administrative Questions and Class Announcements
Topic: Do we have discussion on the day of the midterm?
Replies: 2
Views: 72

Do we have discussion on the day of the midterm?

Do we have discussion on the day of the midterm?
by Lisa Werner 2F
Tue Feb 05, 2019 7:30 pm
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: U total - 3/2nRT
Replies: 3
Views: 78

Re: U total - 3/2nRT

Also, I believe it can only be used for ideal gases.
by Lisa Werner 2F
Tue Feb 05, 2019 7:25 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Internal Energy
Replies: 3
Views: 114

Re: Internal Energy

Dr. Lavelle explained it in lecture and it is required for several homework problems, so I think he considers it fair game for the midterm.
by Lisa Werner 2F
Tue Feb 05, 2019 7:22 pm
Forum: Calculating Work of Expansion
Topic: Work
Replies: 3
Views: 82

Re: Work

Is there a conceptional reason as to why a reversible reaction does more work than a reversible one? The textbook gave the example of a reversible reaction occurring in a container with the same pressure inside and outside, making the system work against the equal pressure to expand. On the other ha...
by Lisa Werner 2F
Sun Jan 27, 2019 4:38 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Bond Enthalpies
Replies: 3
Views: 48

Re: Bond Enthalpies

Bond enthalpy is the least accurate method because it based on the average enthalpies required to break a type of bond across all different types of molecules, rather than a specific molecule.
by Lisa Werner 2F
Sun Jan 27, 2019 4:10 pm
Forum: Phase Changes & Related Calculations
Topic: Why are phase changes endothermic?
Replies: 11
Views: 168

Re: Why are phase changes endothermic?

Phase changes involving the breaking of bonds (solid->liquid->gas) are endothermic because they require/absorb heat. Phase changes involving the formation of bonds (gas->liquid->solid) are exothermic because the release heat.
by Lisa Werner 2F
Sun Jan 27, 2019 4:06 pm
Forum: Phase Changes & Related Calculations
Topic: Week 4 Homework
Replies: 12
Views: 228

Re: Week 4 Homework

Technically speaking, I believe that any homework problems are accepted, but we should begin to work on the thermodynamics outline to stay up to date in the class.
by Lisa Werner 2F
Tue Jan 22, 2019 8:03 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Polyprotic Solutions on Test 1?
Replies: 1
Views: 60

Polyprotic Solutions on Test 1?

I noticed that one homework problem and one worksheet for this section had questions regarding polyprotic solutions, but I didn't think that they were covered in lecture. Does anyone know if they will be on Test 1 or not?
by Lisa Werner 2F
Tue Jan 15, 2019 2:57 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Reaction Quotient
Replies: 8
Views: 184

Re: Reaction Quotient

K specifically describes the reaction at equilibrium, whereas Q can describe the reaction at any time.
by Lisa Werner 2F
Tue Jan 15, 2019 2:55 pm
Forum: Ideal Gases
Topic: pressure
Replies: 7
Views: 147

Re: pressure

Pressure can be changed by changing the temperature or adding an inert gas without changing the volume.
by Lisa Werner 2F
Tue Jan 15, 2019 2:52 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: test 1 [ENDORSED]
Replies: 7
Views: 201

Re: test 1 [ENDORSED]

I am assuming that the test will include acids and bases because last quarter Dr. Lavelle tested everything covered in lecture up until the Friday before the test.
by Lisa Werner 2F
Thu Jan 10, 2019 8:58 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Spontaneous reverse reaction? [ENDORSED]
Replies: 4
Views: 80

Re: Spontaneous reverse reaction? [ENDORSED]

It means that the reverse reaction is thermodynamically favored, so it is happening at a greater rate than the forward reaction.
by Lisa Werner 2F
Thu Jan 10, 2019 8:56 pm
Forum: Student Social/Study Group
Topic: New to Lavelle
Replies: 32
Views: 3563

Re: New to Lavelle

I recommend doing as many practice problems as possible by doing those from the book and attending workshops with practice handouts.
by Lisa Werner 2F
Thu Jan 10, 2019 8:52 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: K vs Kp [ENDORSED]
Replies: 4
Views: 95

Re: K vs Kp [ENDORSED]

Yes, you can assume Kp as essentially the only way to find the K of homogenous gas is through the partial pressure. Similarly, you can assume Kc when dealing with the K of homogenous aqueous reactions because you use molarity to find it.
by Lisa Werner 2F
Sat Dec 08, 2018 8:43 pm
Forum: Naming
Topic: bis-, tris-, etc.
Replies: 4
Views: 230

bis-, tris-, etc.

do we use the bis-, tris-, etc. if a ligand is a polydentate or if it has another greek prefix? basically does oxalate need them or not?
by Lisa Werner 2F
Sat Dec 08, 2018 5:51 pm
Forum: Dipole Moments
Topic: London Dispersion
Replies: 5
Views: 364

Re: London Dispersion

If a molecule has many atoms with high polarizability, the LDF can actually be quite strong.
by Lisa Werner 2F
Sat Dec 08, 2018 5:48 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: HOCl vs HOI
Replies: 9
Views: 453

Re: HOCl vs HOI

Cl is more electronegative, making the electron density around the H atom less. Therefore, it can more easily be donated.
by Lisa Werner 2F
Sat Dec 08, 2018 5:46 pm
Forum: Lewis Acids & Bases
Topic: Binary Acids with H
Replies: 1
Views: 50

Binary Acids with H

In the textbook, it says if A (the element bonded to H) is more electronegative, then the acid will be stronger. However, this rule doesn't work considering between HF and HCl, F is more electronegative than Cl, but HF is a weaker acid than HCl. Why does the rule not apply?
by Lisa Werner 2F
Sat Dec 08, 2018 5:35 pm
Forum: Lewis Acids & Bases
Topic: H vs H30+
Replies: 2
Views: 72

Re: H vs H30+

To expand from the previous reply, their concentrations are therefore interchangeable in the pH equation.
by Lisa Werner 2F
Sat Dec 08, 2018 5:30 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Strengths of H2S vs H2Se
Replies: 1
Views: 185

Re: Strengths of H2S vs H2Se

London dispersion forces are intermolecular forces so they only affect how the molecule interacts with others, not affect bond strength.
by Lisa Werner 2F
Sat Dec 08, 2018 5:25 pm
Forum: Calculating the pH of Salt Solutions
Topic: pH formula?
Replies: 7
Views: 268

Re: pH formula?

I think you also need to know that pH + pOH = 14.
by Lisa Werner 2F
Sat Dec 08, 2018 5:24 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: VSEPR Shape vs Molecular Geometry
Replies: 3
Views: 122

Re: VSEPR Shape vs Molecular Geometry

They are the same thing. Electron geometry would be when lone pairs are considered when determining shape, but it seems like this is almost never considered.
by Lisa Werner 2F
Sat Dec 08, 2018 5:10 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: Churro question 38
Replies: 1
Views: 183

Re: Churro question 38

We have to assume from the problem that the LDF of H2Se overwhelm that of H2S because Se has a higher polarizability than S, so it has stronger LDF.
by Lisa Werner 2F
Sat Dec 08, 2018 5:08 pm
Forum: SI Units, Unit Conversions
Topic: Final Time
Replies: 1
Views: 218

Final Time

In regards to time, does anyone know if the final will have a similar amount of time allotted to each question as the midterm? Or will we have more time?
by Lisa Werner 2F
Sat Dec 08, 2018 5:01 pm
Forum: Sigma & Pi Bonds
Topic: Test 3 Q3D
Replies: 4
Views: 254

Re: Test 3 Q3D

There should be overlap if you are referring to the the diagram of the s hybridizing with the p orbital. If you are referring to the diagram of the bond between two atoms, there should not be overlap.
by Lisa Werner 2F
Sat Dec 08, 2018 4:54 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: Uncertainty
Replies: 1
Views: 244

Re: Uncertainty

When you give your answer you will always use the greater than or equal to sign, unless the question is asking for the minimum uncertainty.
by Lisa Werner 2F
Sat Dec 08, 2018 4:52 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Concept of Chelation
Replies: 3
Views: 68

Re: Concept of Chelation

From my understanding, chelation occurs when a polydentate ligand bonds with a central metal in more than two places, creating a ring. Therefore, only polydentate ligands can be chelating.
by Lisa Werner 2F
Sat Dec 08, 2018 4:38 pm
Forum: Naming
Topic: polydentate?
Replies: 2
Views: 49

Re: polydentate?

you can tell if a ligand is polydentate by looking at the figure and finding the places where it could bond to a central metal, considering the angles.for example, if a ligand could bond in two places, but they are on different side of the molecule, it is still monodentate.
by Lisa Werner 2F
Sun Nov 11, 2018 7:18 pm
Forum: Administrative Questions and Class Announcements
Topic: Midterm [ENDORSED]
Replies: 14
Views: 476

Re: Midterm [ENDORSED]

my TA said that the midterms will be handed out after lecture on Wednesday
by Lisa Werner 2F
Sun Nov 11, 2018 7:13 pm
Forum: Lewis Structures
Topic: Formal charges
Replies: 15
Views: 243

Re: Formal charges

usually you do not have to write the formal charge of each atom for points unless instructed to do so, but it will help you find the correct lewis structure by demonstrating which structure will have the lowest energy.
by Lisa Werner 2F
Sun Nov 11, 2018 7:08 pm
Forum: Electronegativity
Topic: Electron Affinity vs. Ionization Energy
Replies: 8
Views: 180

Re: Electron Affinity vs. Ionization Energy

Also note that C,N,O and F all have exceptions to the trends!
in order from least to greatest in electronic affinity: N,C,O,F
in order from least to greatest in ionization energy: C,O,N,F
by Lisa Werner 2F
Sat Nov 03, 2018 9:58 pm
Forum: Lewis Structures
Topic: Brackets around ions
Replies: 2
Views: 54

Re: Brackets around ions

I would assume that you should always include the brackets during the exam just to safe.
by Lisa Werner 2F
Sat Nov 03, 2018 9:56 pm
Forum: Octet Exceptions
Topic: Formal charge
Replies: 7
Views: 183

Re: Formal charge

Yes because it will determine where the double bond should go
by Lisa Werner 2F
Sat Nov 03, 2018 9:31 pm
Forum: Lewis Structures
Topic: Expanded Valence Shells
Replies: 2
Views: 47

Re: Expanded Valence Shells

I don't think that there is limit. Either way, I think it is arbitrary because finding the lowest formal charge will keep you from ever getting close to what the limit would be, so I wouldn't worry about it.
by Lisa Werner 2F
Mon Oct 22, 2018 2:30 pm
Forum: *Particle in a Box
Topic: Midterm
Replies: 17
Views: 1133

Re: Midterm

I believe it will be cumulative from the beginning of the course.
by Lisa Werner 2F
Mon Oct 22, 2018 2:27 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: What is the equation used for?
Replies: 9
Views: 201

Re: What is the equation used for?

More specifically, it determines the MINIMUM uncertainty of the position.
by Lisa Werner 2F
Mon Oct 22, 2018 2:20 pm
Forum: Properties of Light
Topic: kg or g [ENDORSED]
Replies: 11
Views: 302

Re: kg or g [ENDORSED]

Kg is used because it is the SI unit.
by Lisa Werner 2F
Mon Oct 15, 2018 3:47 pm
Forum: Student Social/Study Group
Topic: Note Taking
Replies: 32
Views: 1731

Re: Note Taking

I prefer taking hand-written notes in class, then going over them the next day and typing them on Google Docs. This is a good review and also ensures organization, clarity, makes it easier to find a specific subject later on.
by Lisa Werner 2F
Mon Oct 15, 2018 3:40 pm
Forum: Administrative Questions and Class Announcements
Topic: Advice from a Medical Student [ENDORSED]
Replies: 147
Views: 84081

Re: Advice from a Medical Student [ENDORSED]

Thank you so much for this insight!
by Lisa Werner 2F
Mon Oct 15, 2018 3:39 pm
Forum: SI Units, Unit Conversions
Topic: How does grading for discussion posts work?
Replies: 80
Views: 2583

Re: How does grading for discussion posts work?

My T.A. said that the deadline for the posts each week is Sunday night!
by Lisa Werner 2F
Sun Oct 07, 2018 9:30 pm
Forum: SI Units, Unit Conversions
Topic: mol vs. mmol
Replies: 12
Views: 465

Re: mol vs. mmol

My TA taught my discussion class that a good way to convert units is to simply substitute the power of 10 associated with the prefix for the prefix when doing calculations. For example, 1 mmol would become 1x10^-3mol.
by Lisa Werner 2F
Sun Oct 07, 2018 9:24 pm
Forum: Molarity, Solutions, Dilutions
Topic: Atomic Weight, Molecular Weight, Formula Weight [ENDORSED]
Replies: 2
Views: 87

Re: Atomic Weight, Molecular Weight, Formula Weight [ENDORSED]

From my understanding, although the atomic weight, molecular weight, and formula weight are slightly different, they can all be found by finding the total weight of the atom(s) in a given atom, molecule, or formula. Therefore, the basic concept is the same.
by Lisa Werner 2F
Sat Oct 06, 2018 1:13 pm
Forum: Significant Figures
Topic: Rounding numbers ending in 5
Replies: 9
Views: 155

Re: Rounding numbers ending in 5

I have always been taught to round up numbers ending in 5 as well.

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