Search found 59 matches

by Anjali 4A
Sun Mar 17, 2019 7:31 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: U=0
Replies: 6
Views: 241

Re: U=0

Yes, I think w always =-q
by Anjali 4A
Sun Mar 17, 2019 7:22 pm
Forum: Administrative Questions and Class Announcements
Topic: Final Grade Release Date?
Replies: 7
Views: 370

Re: Final Grade Release Date?

The final grades should be out before April 1st. I think we'll get an email of where and when to pick up our exams, last quarter I think it was week 2 or 3!
by Anjali 4A
Sun Mar 17, 2019 7:18 pm
Forum: Administrative Questions and Class Announcements
Topic: Chemistry community posts
Replies: 5
Views: 338

Re: Chemistry community posts

I remember Dr. Lavelle saying that we have to post 3 times per week and that's what is written on the syllabus, but if last quarter it just had to add up to 30 in total, I'm not completely sure if its the same for this quarter too.
by Anjali 4A
Sun Mar 10, 2019 10:05 pm
Forum: Administrative Questions and Class Announcements
Topic: Final Questions
Replies: 10
Views: 365

Re: Final Questions

Dr Lavelle said that there will be 8 questions, however, each question is composed of multiple sections! I find it helpful to look at previous finals to familiarize yourself with the formatting as well
by Anjali 4A
Sun Mar 10, 2019 10:03 pm
Forum: Administrative Questions and Class Announcements
Topic: Final
Replies: 18
Views: 555

Re: Final

I don't think there's an exact percentage as everything is fair game, but the newer material might be emphasized more.
by Anjali 4A
Sun Mar 10, 2019 10:02 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Final Exam
Replies: 23
Views: 292

Re: Final Exam

The final is cumulative, so everything covered this quarter will be included!
by Anjali 4A
Sun Mar 03, 2019 11:10 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Does anyone know if test 2 will be curved?
Replies: 15
Views: 310

Re: Does anyone know if test 2 will be curved?

Each test/exam usually isn't curved. However, if our final grades are curved, it will be in our favor and should only be to improve our scores
by Anjali 4A
Sun Mar 03, 2019 11:07 pm
Forum: Balancing Redox Reactions
Topic: Order in Cell diagrams
Replies: 3
Views: 84

Re: Order in Cell diagrams

The order is usually like the following: (s)|(g)|(aq),(aq)||(aq),(aq)|(g)|(s). Liquids aren't included.
by Anjali 4A
Sun Mar 03, 2019 11:05 pm
Forum: Balancing Redox Reactions
Topic: Short hand notation
Replies: 8
Views: 161

Re: Short hand notation

The salt bridge connects the 2 half cells and provides a path for migration of cations and anions. Voltaic cells generate electricity and the salt bridge reduces the voltage produced.
by Anjali 4A
Sun Feb 24, 2019 11:05 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Cell diagram
Replies: 4
Views: 60

Re: Cell diagram

The anode (oxidation, -ve electrode) is on the left, and cathode (reduction, +ve electrode) is on the right.
by Anjali 4A
Sun Feb 24, 2019 10:43 pm
Forum: Student Social/Study Group
Topic: Test #2
Replies: 7
Views: 146

Re: Test #2

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).
by Anjali 4A
Sun Feb 24, 2019 10:42 pm
Forum: Student Social/Study Group
Topic: Test
Replies: 17
Views: 417

Re: Test

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).
by Anjali 4A
Sun Feb 17, 2019 11:15 pm
Forum: Student Social/Study Group
Topic: Test
Replies: 17
Views: 417

Re: Test

Test 2 includes materials after the midterm, and like everyone said, Dr. Lavelle said that - Test 2 covers all topics on Gibbs free energy and electrochemistry up to the Nernst equation.
by Anjali 4A
Sun Feb 17, 2019 11:13 pm
Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
Topic: Midterm Grades
Replies: 35
Views: 740

Re: Midterm Grades

It usually takes a week, so maybe we'll get it during our discussion sessions week 7 or Friday after class!
by Anjali 4A
Sun Feb 17, 2019 11:11 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: HW for W7
Replies: 7
Views: 127

Re: HW for W7

Like everyone said, Dr. Lavelle said to "Hand in Week 7 homework in discussion section on Thermodynamics including Gibbs Free Energy."
by Anjali 4A
Sun Feb 10, 2019 11:25 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: Midterm 2019
Replies: 9
Views: 202

Re: Midterm 2019

On the class website its posted that the midterm covers: Chemical Equilibrium, Acid and Base Equilibria, Thermochemistry, Thermodynamics to the end of entropy.
by Anjali 4A
Sun Feb 10, 2019 11:21 pm
Forum: Ideal Gases
Topic: Lyndon's review session
Replies: 7
Views: 259

Re: Lyndon's review session

Also he usually posts the answers after the review session, but to get the solution and how to get to the final answer I recommend going to his review session!
by Anjali 4A
Sun Feb 10, 2019 11:18 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Midterm #1 14B
Replies: 17
Views: 552

Re: Midterm #1 14B

His midterm review is under the key word "hotdog". He usually posts just the answers for each question after the review session but he will go through each problem (with working out) during his review session!
by Anjali 4A
Sun Feb 03, 2019 10:08 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Material on Midterm?
Replies: 9
Views: 168

Re: Material on Midterm?

As stated on the class website: Midterm covers: Chemical Equilibrium, Acid and Base Equilibria, Thermochemistry, Thermodynamics to the end of entropy
by Anjali 4A
Sun Feb 03, 2019 10:04 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Midterm [ENDORSED]
Replies: 49
Views: 1378

Re: Midterm [ENDORSED]

HW problems are a good way of preparing and practicing similar types of problems for the midterm. Also I believe that Dr Lavelle always puts 1 question from the hw on the exams.
by Anjali 4A
Sun Feb 03, 2019 10:02 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Midterm
Replies: 12
Views: 217

Re: Midterm

There are numerous review sessions held by the TA's and the UA's all of which Dr. Lavelle will post in this upcoming week! The review sessions cover certain topics so it is useful to go to the one's you have most trouble with. I find that going through hw problems is the most effective way to study ...
by Anjali 4A
Sun Jan 27, 2019 11:47 pm
Forum: Phase Changes & Related Calculations
Topic: Due date for Discussion Questions
Replies: 8
Views: 156

Re: Due date for Discussion Questions

Homework questions are due in discussion sections every week and chemistry community is due every Sunday at 11:59
by Anjali 4A
Sun Jan 27, 2019 10:37 pm
Forum: Ideal Gases
Topic: Chemistry Community Posting
Replies: 7
Views: 155

Re: Chemistry Community Posting

The cutoff is 11:59pm every Sunday!
by Anjali 4A
Sun Jan 27, 2019 10:35 pm
Forum: Ideal Gases
Topic: Approximations for ICE
Replies: 20
Views: 252

Re: Approximations for ICE

Like everyone said, we make the approximation when K is small - less than 10^-3.
by Anjali 4A
Sun Jan 20, 2019 8:00 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Pressure
Replies: 8
Views: 128

Re: Pressure

reaction response to minimize the effect of an increasing pressure by decreasing volume. When volume decreases and there are more moles of gas on the left then the reaction --> and favors products. When volume decreases and there are more moles of gas on the right then the reaction <---- favors reac...
by Anjali 4A
Sun Jan 20, 2019 7:19 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Concentrations Effect on K
Replies: 8
Views: 124

Re: Concentrations Effect on K

Like explained in lecture, change in concentration as well as change in pressure - k does not change.
by Anjali 4A
Sun Jan 20, 2019 6:59 pm
Forum: Student Social/Study Group
Topic: test 1
Replies: 10
Views: 421

Re: test 1

Like everyone else said, and according to the announcement: Test 1 covers Equilibrium and Acid & Base Equilibria which is outline 1&2.
by Anjali 4A
Sun Jan 13, 2019 9:47 pm
Forum: Student Social/Study Group
Topic: New to Lavelle
Replies: 32
Views: 3563

Re: New to Lavelle

Going through lecture notes, as well as hw problems, and step up sessions (if you can't attend a few some worksheets are posted on chemistry community) help a lot!
by Anjali 4A
Sun Jan 13, 2019 9:38 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: solids and liquids
Replies: 5
Views: 121

Re: solids and liquids

Because molar concentration of a pure substance (solid or liquid) does not change in a reaction and is therefore not included in equ. constant
by Anjali 4A
Sun Jan 13, 2019 9:37 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Determining Which side is favored
Replies: 5
Views: 99

Re: Determining Which side is favored

To determine which direction a reaction will proceed, we have to calculate the reaction quotient (Q) at any time during reaction and compare it to K. If Q<K there are more reactants than products, therefore more products will be formed and the forward reaction is favored.
by Anjali 4A
Sun Dec 09, 2018 10:39 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: AX3E
Replies: 18
Views: 324

Re: AX3E

It is sp3 hybridized and because there is a lone pair, the shape is trigonal pyramidal.
by Anjali 4A
Sat Dec 08, 2018 8:30 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Shape - 4
Replies: 3
Views: 107

Re: Shape - 4

The UA's/TA's said that we will get the mark if we list either tetrahedral or square planar!
by Anjali 4A
Sat Dec 08, 2018 8:25 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: Why are LDFs everywhere?
Replies: 3
Views: 284

Re: Why are LDFs everywhere?

Are there any exceptions where LDF does not occur in a molecule? From test 3 I was told that formaldehyde does not have London dispersion forces.
by Anjali 4A
Sun Dec 02, 2018 11:14 pm
Forum: Hybridization
Topic: Hybridization
Replies: 11
Views: 192

Re: Hybridization

The VSPER formula for trigonal planar is AX3. Because it has 3 regions of electron density, it has a hybridization of sp2. If a molecule has 2 regions of electron density it will have a hybridization of sp, 3 = sp2, 4=sp3, 5=sp3d, 6=sp3d2.
by Anjali 4A
Sun Dec 02, 2018 11:10 pm
Forum: Hybridization
Topic: lone pairs
Replies: 20
Views: 314

Re: lone pairs

To figure out hybridization, we need to calculate the steric number which is the number of sigma bonds and number of lone pairs, therefore do have to take lone pairs into account when figuring out the hybridization.
by Anjali 4A
Sun Dec 02, 2018 11:05 pm
Forum: Hybridization
Topic: hybridization
Replies: 13
Views: 424

Re: hybridization

Draw the lewis structure, and calculate the steric number which is the number of sigma bonds and number of lone pairs. Based on the steric number we can figure out the hybridization. E.g. steric number 2 = sp, 3= sp2 and so on.
by Anjali 4A
Mon Nov 26, 2018 11:38 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Test 3
Replies: 38
Views: 764

Re: Test 3

We should revise everything covered on the outline Dr. Lavelle gave, and I find that revising lecture notes and doing as many problems as I can helps the most!
by Anjali 4A
Mon Nov 26, 2018 11:32 pm
Forum: Dipole Moments
Topic: TEST 3: Polarity
Replies: 7
Views: 166

Re: TEST 3: Polarity

I agree! the arrow should always point toward the atom with a negative charge.
by Anjali 4A
Mon Nov 26, 2018 11:28 pm
Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
Topic: test #3
Replies: 14
Views: 505

Re: test #3

We should understand the reason for bond angles for each VSPER shape and eventually memorize the angles.
by Anjali 4A
Sun Nov 18, 2018 9:17 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: 7th edition 2E. 21
Replies: 4
Views: 62

Re: 7th edition 2E. 21

Dr. Lavelle said he does not expect us to know the specific bond angles, and on exams he will accept answers 'less than'.
by Anjali 4A
Sun Nov 18, 2018 9:11 pm
Forum: Properties of Light
Topic: Test 3
Replies: 24
Views: 581

Re: Test 3

I don't think we'll be directly tested on Lewis Structures, however, we would still need to know how to draw them in order to determine the shape.
by Anjali 4A
Tue Nov 13, 2018 11:39 am
Forum: Administrative Questions and Class Announcements
Topic: Test 3
Replies: 8
Views: 230

Re: Test 3

Dr Lavelle said that - Test 3 covers: End of Bonding from 3.12 (6 Ed.) and from 2D (7 Ed.); and all of Molecular Shape and Structure (see Syllabus and Outlines for details).
by Anjali 4A
Sun Nov 11, 2018 11:30 pm
Forum: Administrative Questions and Class Announcements
Topic: Class Grading
Replies: 9
Views: 358

Re: Class Grading

The syllabus says that the class is not curved, however, from past experience if a class is based on a straight scale (A+ 97% A 93-96% A- 90-92 % and so on) and the average is lower than a B the class will be curved in our favor. But I am not too sure if this applies to Chem14a.
by Anjali 4A
Sun Nov 11, 2018 11:22 pm
Forum: Properties of Light
Topic: Test 3
Replies: 24
Views: 581

Re: Test 3

Dr. Lavelle should post the topics of test 3 soon before the test, but like everyone said it will most likely be topics completed after the midterm
by Anjali 4A
Sun Nov 11, 2018 11:19 pm
Forum: Resonance Structures
Topic: Drawing resonance
Replies: 17
Views: 619

Re: Drawing resonance

In a exam/test situation, I think that it'll be safer to draw the resonance structure of the molecule.
by Anjali 4A
Sun Nov 04, 2018 10:34 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: Test 2 Alveoli question
Replies: 5
Views: 276

Re: Test 2 Alveoli question

Some questions give the radius instead of the diameter, in that case would we multiply the radius by 2?
by Anjali 4A
Sun Nov 04, 2018 10:30 pm
Forum: Electronegativity
Topic: Periodic Trends
Replies: 10
Views: 292

Re: Periodic Trends

I usually draw the periodic trends out, so for ionization energy and electronegative since it increases as you go across, and decreases as you go down, I would draw two arrows across the periodic table - the side with the arrow indicating the higher ionization energy/electronegativity. I would then ...
by Anjali 4A
Sun Nov 04, 2018 10:25 pm
Forum: Administrative Questions and Class Announcements
Topic: chem test tmrw
Replies: 6
Views: 218

Re: chem test tmrw

There will be the same formula page like we had for both test 1 and 2!
by Anjali 4A
Sun Oct 28, 2018 9:52 pm
Forum: General Science Questions
Topic: Khan Academy
Replies: 10
Views: 386

Re: Khan Academy

I personally find Khan Academy a useful addition to studying as, especially if you're a visual learner, Khan academy helps to clarify information that initially seems hard to understand. But I would also recommend to make sure that the videos you are watching are relevant to class material.
by Anjali 4A
Sun Oct 28, 2018 9:42 pm
Forum: Trends in The Periodic Table
Topic: Atomic Radius
Replies: 8
Views: 158

Re: Atomic Radius

I believe that we don't have to know the specific values as they will be provided to us if needed. Knowing the trends and justifications will be helpful.
by Anjali 4A
Sun Oct 28, 2018 9:25 pm
Forum: Administrative Questions and Class Announcements
Topic: Midterm
Replies: 11
Views: 258

Re: Midterm

Dr. Lavelle posted on the class website that the midterm covers: Fundamentals, Quantum, Bonding to end of 3.11 (6 Ed.) and to end of 2C (7 Ed.)
by Anjali 4A
Mon Oct 22, 2018 12:58 am
Forum: Properties of Light
Topic: Do I have to memorize the spectrum?
Replies: 20
Views: 393

Re: Do I have to memorize the spectrum?

I think that we would be provided with it, but should at least familiarize and understand it beforehand.
by Anjali 4A
Sun Oct 21, 2018 1:17 am
Forum: Student Social/Study Group
Topic: Next week's quiz
Replies: 5
Views: 182

Re: Next week's quiz

On the syllabus, it states that the quantum world covers chapter 1 & 2 in the sixth edition, and Focus 1 (omit 1C and 1D.1) in the seventh edition. I think that this test covers the aforementioned chapters with respect to the following topics - photoelectric effect, Heisenberg's uncertainty prin...
by Anjali 4A
Thu Oct 18, 2018 11:52 am
Forum: Administrative Questions and Class Announcements
Topic: Grading
Replies: 3
Views: 165

Re: Grading

If a class is not graded on a curve, I'm assuming it's graded using a straight scale: 87-89% = B+, 83-86% = B, 80-82% = B- and so on. I think that this means that it will not hurt if others do better than you. On the syllabus the outline for the final point system is stated, which is out of 500: Wee...
by Anjali 4A
Sun Oct 14, 2018 5:01 pm
Forum: Properties of Light
Topic: Speed of Light
Replies: 41
Views: 793

Re: Speed of Light

Will we be provided all of these constants/equations during the tests, midterms and final?
by Anjali 4A
Sun Oct 14, 2018 4:55 pm
Forum: Significant Figures
Topic: When to round the answers to significant figures
Replies: 11
Views: 508

Re: When to round the answers to significant figures

I agree! Keeping extra sig figs during the calculation steps helps to yield the most accurate answer (and rounding the answer at the end). While calculating, I often use the answer stored in my calculator to calculate the next step, so that the most accurate answer will continued to be used for the ...
by Anjali 4A
Sat Oct 06, 2018 10:20 pm
Forum: Empirical & Molecular Formulas
Topic: Empirical formula set up
Replies: 9
Views: 198

Re: Empirical formula set up

I think that since the empirical formula is the relative number of atoms, the easiest method is to solve the problem by imagining that the sample mass is 100g.
by Anjali 4A
Sat Oct 06, 2018 10:06 pm
Forum: Balancing Chemical Reactions
Topic: Balancing reactions tips
Replies: 29
Views: 885

Re: Balancing reactions tips

I also usually balance equations using the trial and error method, but like Dr. Lavelle said in class we should always balance the element that occurs the least in the equation. For example, if O Occurs in many species (e.g. 3) and H & C occurs in less species (e.g. 2) we should balance O first ...
by Anjali 4A
Sat Oct 06, 2018 9:55 pm
Forum: General Science Questions
Topic: Rusty on High School Chem [ENDORSED]
Replies: 166
Views: 100980

Re: Rusty on High School Chem [ENDORSED]

I would recommend to look at online videos in addition to the ones posted on the class websites that provide a step by step outline of how to solve different questions. While watching the video, writing the process of the answer out at the same time extremely helps as well. And of course, practicing...

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