Search found 30 matches

by Derek Lee 2K
Thu Mar 16, 2017 12:43 am
Forum: General Science Questions
Topic: Final
Replies: 9
Views: 1380

Re: Final

6 questions!! It's all in that finals post that disappeared somewhere
by Derek Lee 2K
Wed Mar 08, 2017 2:08 pm
Forum: *Alkanes
Topic: Quiz 3 Drop -- do I show up? [ENDORSED]
Replies: 3
Views: 405

Re: Quiz 3 Drop -- do I show up? [ENDORSED]

I would email your TA. It wouldn't hurt to take it for the practice.
by Derek Lee 2K
Sat Mar 04, 2017 4:51 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: Quiz 3 [ENDORSED]
Replies: 14
Views: 986

Re: Quiz 3 [ENDORSED]

The kinetics stuff should only be like the last couple concepts like the Arrhenius equation.
by Derek Lee 2K
Mon Feb 27, 2017 2:53 pm
Forum: Biological Examples
Topic: Enzymes
Replies: 2
Views: 555

Re: Enzymes

Heterogenous enzymes exist as well. Whenever it catalyzes a reaction and is in a different state from the reactant then it's heterogenous.
by Derek Lee 2K
Sun Feb 26, 2017 8:30 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: determining the catalyst
Replies: 4
Views: 425

Re: determining the catalyst

You can tell by looking at the steps and identifying which molecule didn't change. Intermediates are like "in between" molecules so their structure changes. But catalysts don't chemically change in a reaction. If you see that they're the same on both the reactant and product side of a reac...
by Derek Lee 2K
Sat Feb 25, 2017 11:24 pm
Forum: Student Social/Study Group
Topic: Chem 14C Lecture 1
Replies: 3
Views: 537

Re: Chem 14C Lecture 1

Are we still able to switch this late into the quarter?
by Derek Lee 2K
Fri Feb 24, 2017 10:58 am
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Pre-equilibrium approach
Replies: 1
Views: 258

Re: Pre-equilibrium approach

I think it will be given for the most part. And if not, the way you describe how to approach the rate law should work out as well too.
by Derek Lee 2K
Thu Feb 16, 2017 1:16 pm
Forum: Administrative Questions and Class Announcements
Topic: Quiz 2 Winter 2017
Replies: 160
Views: 15312

Re: Quiz 2 Winter 2017

Does quiz 2 just cover up to the end of kinetics? Is it cumulative?
by Derek Lee 2K
Sun Feb 12, 2017 11:17 pm
Forum: Phase Changes & Related Calculations
Topic: Equation to find standard reduction potentials?
Replies: 2
Views: 290

Re: Equation to find standard reduction potentials?

I believe they should all be given for the most part.
by Derek Lee 2K
Sun Feb 05, 2017 8:09 pm
Forum: Administrative Questions and Class Announcements
Topic: Quiz 1
Replies: 5
Views: 579

Re: Quiz 1

They don't post but I heard that they're passing them back out after lecture on Wednesday I believe.
by Derek Lee 2K
Wed Feb 01, 2017 2:24 pm
Forum: Calculating Work of Expansion
Topic: When to Use Different Formulas for Work
Replies: 2
Views: 336

Re: When to Use Different Formulas for Work

It basically boils down to irreversible reactions which is the first equation and reversible ones which is the second.
by Derek Lee 2K
Mon Jan 30, 2017 5:59 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: How to interpret ∆H
Replies: 2
Views: 459

Re: How to interpret ∆H

When it refers to 1 mol of reactants I believe it has a different notation. (the delta H with the little circle). Delta H on its own is just the enthalpy of the reaction as a whole.
by Derek Lee 2K
Thu Jan 26, 2017 5:31 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Practice Quiz
Replies: 1
Views: 222

Re: Practice Quiz

I thought you solved for the change in pressure and the change in volume both for the two entropies and they can be put together?
by Derek Lee 2K
Tue Jan 17, 2017 1:58 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Values Given on Exams?
Replies: 2
Views: 319

Re: Values Given on Exams?

He said he'd give it to us, but since you have it memorized you're all good.
by Derek Lee 2K
Tue Jan 17, 2017 1:11 pm
Forum: Phase Changes & Related Calculations
Topic: Phase Change Question
Replies: 1
Views: 299

Re: Phase Change Question

It has to do with the bonds in each phase. Solid to liquid, you're just loosening the bonds to the point that they can slide next to each other (liquid). However, it requires more energy to vaporize than to melt because you're completely breaking apart the bonds in water which requires much more ene...
by Derek Lee 2K
Fri Dec 02, 2016 9:40 pm
Forum: Lewis Acids & Bases
Topic: Strong Acids and Bases
Replies: 1
Views: 310

Re: Strong Acids and Bases

I believe you still use double since it's still an equilibrium reaction. At least this is what my TA said.
by Derek Lee 2K
Sun Nov 27, 2016 6:41 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: Sig figs in calculations for pH and pOH
Replies: 2
Views: 312

Re: Sig figs in calculations for pH and pOH

It always seems to round off to three sig figs for me. But not sure, commenting on this post to follow because I have the same question.
by Derek Lee 2K
Sun Nov 20, 2016 7:21 pm
Forum: Naming
Topic: Mono
Replies: 2
Views: 316

Re: Mono

It is only really necessary when you're describing how many bonds it can make. ex) Monodentate
by Derek Lee 2K
Wed Nov 16, 2016 12:31 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Quiz 3 Prep Fall 2014 #10
Replies: 2
Views: 451

Re: Quiz 3 Prep Fall 2014 #10

I did that but I still end up with a value for x that is too small. What numbers did you have after doing PV=nRT?
by Derek Lee 2K
Tue Nov 08, 2016 1:18 am
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Homework 17.33
Replies: 7
Views: 645

Re: Homework 17.33

The way I've been doing it and how the solution manual shows you is to do a basic sketch of the structure and then you look at which atoms have lone pairs. Lone pairs means its free to bind to another atom so you count up the atoms with lone pairs and that corresponds to what type of polydentate it ...
by Derek Lee 2K
Sat Nov 05, 2016 3:48 pm
Forum: Student Social/Study Group
Topic: Midterm over!!
Replies: 11
Views: 1405

Re: Midterm over!!

All the naming material that we're covering now and molecular orbital theory is what my TA told me.
by Derek Lee 2K
Thu Oct 27, 2016 6:34 pm
Forum: Administrative Questions and Class Announcements
Topic: MidTerm Review [ENDORSED]
Replies: 4
Views: 590

Re: MidTerm Review [ENDORSED]

He said up to chapter 4. Basically fundamentals to chapter 4.
by Derek Lee 2K
Thu Oct 20, 2016 10:56 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Excited vs. Ground State [ENDORSED]
Replies: 1
Views: 294

Re: Excited vs. Ground State [ENDORSED]

Ground state just means that the electron is in the lowest energy form possible. That means that the electron is in the orbital we would normally expect it to be. Excited states are when electrons are not in the correct orbital. So, in 39 for example, the carbon is excited because the second 2p elec...
by Derek Lee 2K
Thu Oct 13, 2016 8:57 pm
Forum: Administrative Questions and Class Announcements
Topic: Rounding and Accuracy During Tests
Replies: 4
Views: 547

Re: Rounding and Accuracy During Tests

Yeah that's true, it just kind of varies from problem to problem. To be honest, your way is probably better but I'm just saying that whichever way you do it, at least the solution manual kind of verifies that you're ok so I wouldn't freak out too much if its confusing you.
by Derek Lee 2K
Sat Oct 08, 2016 8:22 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Rydberg Equation [ENDORSED]
Replies: 4
Views: 541

Re: Rydberg Equation [ENDORSED]

My TA said to always use it because they give partial credit if we at least find the energy of each n level. He said that if we use ryberg's, if we mess up the calculation in any way and get the wrong answer, then the whole thing is wrong and there's no partial credit.
by Derek Lee 2K
Fri Oct 07, 2016 4:00 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Orbital Question [ENDORSED]
Replies: 3
Views: 459

Re: Orbital Question [ENDORSED]

What's the difference between the two? I didn't fully understand. Does it just have to do with the spin or something?
by Derek Lee 2K
Fri Oct 07, 2016 9:13 am
Forum: Administrative Questions and Class Announcements
Topic: Rounding and Accuracy During Tests
Replies: 4
Views: 547

Re: Rounding and Accuracy During Tests

From looking at the solutions in the textbook solutions manual and workbook, it constantly wants us to round off to the proper number of sig figs at each step of the problem. If you do that, it's easier to keep track of sig figs from the beginning because you just end up with the smallest number of ...
by Derek Lee 2K
Thu Sep 29, 2016 1:09 am
Forum: Empirical & Molecular Formulas
Topic: Order of writing ions in a molecule? [ENDORSED]
Replies: 3
Views: 523

Re: Order of writing ions in a molecule? [ENDORSED]

I'm not sure if this is correct but I was taught in high school chem that you can generally put them back into the order they were presented to you. I've done some problems from the book and the solution manual generally does the same too.
by Derek Lee 2K
Thu Sep 29, 2016 1:05 am
Forum: Significant Figures
Topic: Sig Figs. Problem
Replies: 4
Views: 691

Re: Sig Figs. Problem

It's always good to keep track of them as you go. At least look at the numbers you're starting out with and make sure that the sig figs at the beginning of the problem match the end of the problem. However, as you're working along the problem, you can be off in terms of sig figs one or two places an...
by Derek Lee 2K
Mon Sep 26, 2016 5:41 pm
Forum: Student Social/Study Group
Topic: Hedrick Summit Study Group Chem 14A
Replies: 29
Views: 2568

Re: Hedrick Summit Study Group Chem 14A

I would like to join this as well! PM me.

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