Search found 30 matches

by Josephine_Tang_1N
Fri Mar 17, 2017 10:29 pm
Forum: Administrative Questions and Class Announcements
Topic: Final Exam Details and Review Sessions Winter 2017
Replies: 114
Views: 13623

Re: Final Exam Details and Review Sessions Winter 2017

Is there a link for Lavelle's review session from today?
by Josephine_Tang_1N
Sun Mar 12, 2017 2:35 pm
Forum: Administrative Questions and Class Announcements
Topic: Final Exam Details and Review Sessions Winter 2017
Replies: 114
Views: 13623

Re: Final Exam Details and Review Sessions Winter 2017

Will the final be more focused on material at the end of the quarter?
by Josephine_Tang_1N
Wed Mar 08, 2017 11:20 am
Forum: *Free Energy of Activation vs Activation Energy
Topic: Delta G Double Dagger, Delta H Double Dagger, Delta S Double Dagger
Replies: 3
Views: 2643

Re: Delta G Double Dagger, Delta H Double Dagger, Delta S Double Dagger

If this is referring to Section 4.4 in the green organic textbook, they state that all the statements they make reference the reaction in Figure 4.6, which is an SN2 reaction.
by Josephine_Tang_1N
Wed Mar 08, 2017 11:04 am
Forum: *Alkanes
Topic: Naming [ENDORSED]
Replies: 92
Views: 8309

Re: Naming [ENDORSED]

Bryan Vega 2E wrote:Would a prefix, such as "di" in dimethyl, affect the order when naming alphabetically?

no!
by Josephine_Tang_1N
Wed Mar 08, 2017 11:02 am
Forum: *Alkanes
Topic: Naming [ENDORSED]
Replies: 92
Views: 8309

Re: Naming [ENDORSED]

Will the order always be in alphabetical order when naming the structures ? Sometimes it can vary if there's a "substituent in a substituent" type of situation (i.e. IUPAC naming for isopropyl branch would be 2-methylpropyl which would be included amongst other substituents if applicable)...
by Josephine_Tang_1N
Wed Mar 01, 2017 12:45 pm
Forum: *Organic Reaction Mechanisms in General
Topic: Drawing Reaction Profiles
Replies: 1
Views: 256

Drawing Reaction Profiles

For a multistep reaction profile where we are estimating it for each step, how can we know how high/low/wide to draw each step?
by Josephine_Tang_1N
Fri Feb 24, 2017 3:07 pm
Forum: Administrative Questions and Class Announcements
Topic: Midterm Winter 2017
Replies: 87
Views: 14429

Re: Midterm Winter 2017

Sebastian wrote:If we weren't able to make it to lecture on Wednesday, what is another option to obtain our midterm?

I would email your TA to ask if they can bring it to office hours or your next discussion
by Josephine_Tang_1N
Fri Feb 24, 2017 3:06 pm
Forum: Administrative Questions and Class Announcements
Topic: Fall 2016 Finals Still Available?
Replies: 5
Views: 686

Re: Fall 2016 Finals Still Available?

They're available at the Information office (Young 3034)! I think they open at 7AM.
by Josephine_Tang_1N
Wed Feb 22, 2017 9:25 pm
Forum: Administrative Questions and Class Announcements
Topic: Midterm Winter 2017
Replies: 87
Views: 14429

Re: Midterm Winter 2017

Have the solutions been posted anywhere yet?
by Josephine_Tang_1N
Sun Feb 19, 2017 4:00 pm
Forum: Administrative Questions and Class Announcements
Topic: Bruincast Audio Problem
Replies: 16
Views: 1600

Re: Bruincast Audio Problem

Just a note: Chrome does work for the audio bruincast (normal or iPod/iPad version), but you'll have to use another browser if you want to see the video!
by Josephine_Tang_1N
Wed Feb 15, 2017 11:27 am
Forum: Third Law of Thermodynamics (For a Unique Ground State (W=1): S -> 0 as T -> 0) and Calculations Using Boltzmann Equation for Entropy
Topic: Midterm Winter 2013 problem 5B
Replies: 10
Views: 916

Re: Midterm Winter 2013 problem 5B

Chem Mod also posted a response on another post saying that larger molecules with more electrons contribute more entropy because (basically) there are more total particles to be knocked around and cause disorder.
by Josephine_Tang_1N
Mon Feb 13, 2017 4:50 pm
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: Reversibility
Replies: 2
Views: 323

Re: Reversibility

I was in a UA review session and he said that usually the adiabatic (q=0) is irreversible--just another note!
by Josephine_Tang_1N
Mon Feb 13, 2017 4:42 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: H2O in Galvanic Cell Diagram
Replies: 1
Views: 311

Re: H2O in Galvanic Cell Diagram

Definitely in acidic solution and basic solution reactions. They're not included in the cell diagrams because technically with aqueous solutions, they are by definition a solute with water so it'd be redundant to add water.
by Josephine_Tang_1N
Thu Feb 09, 2017 9:04 pm
Forum: Balancing Redox Reactions
Topic: Homework 14.15 (a)
Replies: 1
Views: 266

Homework 14.15 (a)

Instructions: "Write the half-reaction and devise a galvanic cell (write a cell diagram) to study each of the following reactions: (a) AgBr_{(s)} \rightleftharpoons Ag^+_{(aq)} + Br^-_{(aq)} , a solubility equilibrium" I don't understand where to draw the two half-r...
by Josephine_Tang_1N
Mon Jan 30, 2017 12:21 am
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Question 8.77
Replies: 1
Views: 340

Question 8.77

For this problem, it can be calculated that the energy of the unhybridized carbon bonds = 2880 kJ while the hybridized bonds = 3108 kJ. Why is the higher energy more stable in this case? Even with consideration that these bonds are the ones formed (therefore negative), the absolute energy is higher ...
by Josephine_Tang_1N
Mon Jan 30, 2017 12:04 am
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Question 8.77
Replies: 1
Views: 263

Re: Question 8.77

They're basically the unhybridized Lewis structures (being asked to compare to hybridized).
by Josephine_Tang_1N
Mon Jan 23, 2017 12:42 am
Forum: Phase Changes & Related Calculations
Topic: delta u sign
Replies: 2
Views: 351

Re: delta u sign

Right - this is since the volume decreases (negative V) and corresponds to a change from: - PV to + PV.
by Josephine_Tang_1N
Fri Jan 13, 2017 4:04 pm
Forum: Administrative Questions and Class Announcements
Topic: Bruincast
Replies: 26
Views: 8104

Re: Bruincast

Will any of the 14B lectures be Webcasted?
by Josephine_Tang_1N
Fri Jan 13, 2017 3:56 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Closed system
Replies: 3
Views: 400

Re: Closed system

I would assume the system is isolated because thermodynamic problems calculate changes in energy
by Josephine_Tang_1N
Fri Nov 25, 2016 8:07 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Discussion Section
Replies: 1
Views: 225

Re: Discussion Section

I think he mentioned something about going to another one of your TA's sections!
by Josephine_Tang_1N
Fri Nov 18, 2016 8:51 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Water in K calculation
Replies: 3
Views: 367

Re: Water in K calculation

If a product or reactant is a solid or liquid, is its contribution to the K calculation automatically 1?
by Josephine_Tang_1N
Mon Nov 14, 2016 12:40 am
Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
Topic: Sigma and Pi order in MO
Replies: 1
Views: 181

Re: Sigma and Pi order in MO

Correct me if I'm wrong but I think 2p bond switches with the 2p once z8 because there are actually electrons occupying the space for pi bonds.
by Josephine_Tang_1N
Tue Nov 01, 2016 6:46 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Fall 2012 Midterm Q5B
Replies: 2
Views: 410

Fall 2012 Midterm Q5B

This questions asks for Lewis structures of a few gaseous molecules to see if they would contribute to global warming. Part (d) asks for SO2, which I drew S as the central atom double bonded with O on both sides - both O's and S have a lone pair in my drawing, which has zero formal charge on each at...
by Josephine_Tang_1N
Mon Oct 31, 2016 1:57 am
Forum: Determining Molecular Shape (VSEPR)
Topic: Larger Molecular Shapes
Replies: 1
Views: 219

Larger Molecular Shapes

If a molecule has enough atoms to have different structures depending on which you count as the central atom, how would you describe the molecular shape? For example, (CH3)2Be is a linear structure when considering Be as the central atom, but the carbon would be considered tetrahedral on its own?
by Josephine_Tang_1N
Thu Oct 20, 2016 5:20 am
Forum: Administrative Questions and Class Announcements
Topic: About the "Rough Guideline"
Replies: 4
Views: 4156

Re: About the "Rough Guideline"

Generally, I base it on how far away the elements are from each other on the periodic table: the farther they are i.e. opposite sides of the periodic table, the more ionic in character.
by Josephine_Tang_1N
Wed Oct 19, 2016 10:18 pm
Forum: Administrative Questions and Class Announcements
Topic: Workbook prep for Quiz #2
Replies: 1
Views: 224

Workbook prep for Quiz #2

I was looking at the practice exams in the workbook for Quiz #2 and saw that some of the questions were on things that aren't covered in Chapter 2 and 3 i.e. sigma and pi bonds, hybridization, bond order, etc. Do we still do these problems and turn them in next week when our discussion is?
by Josephine_Tang_1N
Sun Oct 16, 2016 11:28 pm
Forum: Administrative Questions and Class Announcements
Topic: Posting on chem com
Replies: 1
Views: 266

Re: Posting on chem com

I'm under the assumption that the post dates coincide with the week count at the top righthand corner of my.ucla.edu (see attached photo)
by Josephine_Tang_1N
Sun Oct 09, 2016 8:54 pm
Forum: Significant Figures
Topic: All students read this sig fig post [ENDORSED]
Replies: 116
Views: 10349

Re: All students read this sig fig post [ENDORSED]

For testing purposes, is there a difference between writing 1.8 x 10^-2 and 0.018? I know they're synonymous, but I've seen both used in the textbook and workbook so I was wondering if there is a preference for either when it comes to giving a final answer.
by Josephine_Tang_1N
Fri Oct 07, 2016 3:48 pm
Forum: Student Social/Study Group
Topic: Hitch Study Group
Replies: 12
Views: 1205

Re: Hitch Study Group

Is anyone down to meet up Sunday night?
by Josephine_Tang_1N
Wed Sep 28, 2016 6:41 pm
Forum: Student Social/Study Group
Topic: Hitch Study Group
Replies: 12
Views: 1205

Re: Hitch Study Group

I'm in Hitch C, but would def wanna meet up and study sometime!

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