CHEMISTRY COMMUNITY

Junghyuk_Park_1I

Is it possible to have more than one cis and trans configuration in one molecule (resulting from multiple double bonds)? If so, how would we go about naming such a molecule?

Junghyuk_Park_1I

On page 94 in the course reader, I am a bit confused on the labeling and was wondering what we need to know. I can see iso, neo, vinyl, and allyl, but what exactly is the structure of an amyl or isoamyl? I apologize if I am just not seeing somethign that is obvious. Thank you in advance!

Junghyuk_Park_1I

What are the general guidelines/rules for determining nucleophilic strength? Electrophilic strength? The textbook notes some rules, but it also says that the rules are not definitive so I am a bit confused. Thank you in advance!

Junghyuk_Park_1I

What exactly are the differences between the steady-state and pre-Equilibrium approaches (and any others I may have excluded)? What are the differences conceptually and when would we use each? Thanks in advance!

Junghyuk_Park_1I

After finding the concentration of A via the concentration of B, why is the following step done?

[A]0 - [(2 mol A/1 mol B)*(0.034 mol B/L)]

Thanks in advance.

Junghyuk_Park_1I

Why is there sometimes a random metal added to the cell diagram notation when it wasn't involved in the reaction given (ex: Pt, Cd, etc)? Thanks in advance!

Junghyuk_Park_1I

Would the Oxidation number for diatomic Oxygen (O2) be 0 because it's a the common form molecule or -2 as in usual cases (besides in peroxide)?

Junghyuk_Park_1I

What exactly are the general guidelines for writing the half reactions to determine E (standard) of the cell? Also, why is the half reaction method recommended over the use of the equation E (standard) cell= E (standard) cathode- E (standard) anode? Thanks in advance!

Junghyuk_Park_1I

When is work positive or negative in terms of thermodynamics? When the system is doing work (what sign)? When work is done on the system (what sign)?

Junghyuk_Park_1I

What exactly is degeneracy conceptually? How is it applied in thermodynamics?

Junghyuk_Park_1I

What exactly does it mean when a reaction is reversible? Thank you in advance.

Junghyuk_Park_1I

What exactly is the difference between c, Cv, and Cp? When would each be used and why are the three different designations necessary? Thanks in advance!

Junghyuk_Park_1I

I had a question on standard enthalpy of formation discussed in class. What exactly is it? Dr. Lavelle mentioned that for some molecules, the standard enthalpy of formation is 0 and thus we cannot find the value on a chart (ex: diatomic hydrogen; H2). Why exactly is this so? Thank you in advance!

Junghyuk_Park_1I

On the final, are we allowed to use the estimation method Dr. Lavelle mentioned in class (where we ignore x in the denominator if presumed to be small and less than 5% of the concentration given) on the final?

Junghyuk_Park_1I

I had the following question in regards to what Dr. Lavelle mentioned in lecture on the Weak Acid/Base-Strong Base/Acid Titrations section of the course reader. He said that we could use a memory tool of: Weak Acid + Strong Base leads to a slightly more basic (slightly above pH 7) stoichiometric poi...

Junghyuk_Park_1I

I had a question regarding the content in the course reader pages 156-157. I'm confused on what Dr. Lavelle meant when he was using the approximation method and saying that after you get a final value, this value can be misleading as you have to keep in mind that the pH of pure water is 10^-7. What ...

Junghyuk_Park_1I

How do we draw the the molecular orbital diagrams for hetero-nuclear molecules (i.e. HF, CO, NO)? Because one of the atoms is Z<8 and the other Z>8, do we put the pi 2p or sigma 2p above or below? How do we know which one it behaves like?

Junghyuk_Park_1I

I was wondering how you determine which orbital is less energy when drawing a molecular orbital energy diagram (i.e. N 2s vs. O 2s)? Thank you in advance.

Junghyuk_Park_1I

What exactly are the conceptual differences between Kc, Kp, and Q? When would you use each of them? Also conceptually, how does comparing Kc or Kp to Q equate to determining which direction a reaction is favored? Thank you in advance.

Junghyuk_Park_1I

I had the following question:
What exactly does the concept of HOMO (highest occupied molecular orbital) to LUMO (lowest unoccupied molecular orbital) refer to? What does the acronym tell us?
Thank you in advance.

Junghyuk_Park_1I

What exactly does bonding and anti-bonding mean/refer to? I am a bit confused on what they mean and how to determine which electrons are in the bonding molecular orbital and anti-bonding molecular orbital. Thanks in advance.

Junghyuk_Park_1I

I know that this might be hard to put into words, but what are the general rules on filling out a Molecular Orbital Energy Level Diagram (i.e. how to fill in electrons into bonding/antibonding orbitals, how to determine which is bonding/antibonding, etc.)?

Junghyuk_Park_1I

I understand that the Lewis Structures depend on formal charge and octet rule (with formal charge being more important), but I had the following question: Which elements tend to be/can be octet exceptions (example Boron can have 3 bonds as well as other elements with expanded octets)? Is there a way...

Junghyuk_Park_1I

I had the following question about writing electron configurations. I know during lecture Dr. Lavelle stated that once the d orbital becomes available for an element, the electron placement on the configuration short hand notation does not simply fill in order (i.e. [Ar] 4s^2 3d^3 vs. [Ar] 3d^5). I ...

Junghyuk_Park_1I

I had the following question about the Rydberg Equation: So I know that there are variations of the same equation that can be derived: (frequency)= R( (1/(n1)^2)-(1/(n2)^2)) En=-((R)(h))/n^2 When would it be most efficient/beneficial to use each variation of the equation? Also how does one determine...

Junghyuk_Park_1I

I agree with the above reply. Basically, electrons are thought to be in orbitals and electron clouds which do not have a definite shape. Thus, because the electrons do not form a convenient circular shell (which we can easily find the radius of), we must average out the distance between what we can ...

Junghyuk_Park_1I

The first equation is used when an electron has not been ejected with an exit velocity off of the solid metal once the light source hits it. The second equation is used when the electrons have been ejected with a kinetic energy (which implies velocity). Basically, both equations are talking about th...

Junghyuk_Park_1I

My TA said to just use as many significant figures as the constant you used. So depending on the value you used (i.e. speed of light=3.0*10^8 m/s as opposed to 2.998*10^8 m/s) in the problem. Thus, if you are using the constant on the equation sheet, he said to use as many significant figures as you...

Junghyuk_Park_1I

I believe what that problem is trying to teach you is that when we try to describe macroscopic objects with quantum mechanical wave functions (which are meant for extremely small objects) the results are not really visible. If you look at de Broglie's wave equation λ= (h)/(mv) with your car example,...

Junghyuk_Park_1I

Okay, I''ll be sure to add you guys to the Group Me sometime in the next day or two.

Junghyuk_Park_1I

I'm a bit confused on the Wave-Particle Duality of light. So light behaves both as a wave AND particle (photon), and we don't know how to properly draw out a beam of light correct? In terms of the equations, my question is the following: So if equations such as c=(wavelength)*(frequency) describe li...

Junghyuk_Park_1I

Okay, I just sent an email with everyone's email posted prior to this message. We could meet in the lounge or something (depending on how crowded). Could you guys message your phone numbers on the mass email so that we can get a convenient group chat started? The goal is probably to meet for the fir...

Junghyuk_Park_1I

We could obviously take on more people, but I think that we definitely have enough to at least start forming a small group. Yeah if you guys could leave some form of contact (email, phone, Facebook, etc) I could form a group chat or something. And once we have everyone, we could meet on one of the l...

Junghyuk_Park_1I

If any of you guys are living in Dykstra Hall, let me know if you want to form a study group. Anyone not living in Dykstra is welcome as well (we could meet in a library).

CHEMISTRY COMMUNITY

Search found 34 matches

Cis and Trans

Course Reader Page 94

Nucleophilic Strength Guidelines

Steady State vs. Pre-Equilibrium Approach

Homework Question 15.23

Cell Diagrams [ENDORSED]

Oxidation Number of Diatomic Oxygen

General Guidelines for Writing Half Reactions

Sign of Work

Degeneracy

Reversible Reaction

Cv vs Cp

Standard Enthalpy of Formation Question

Acid/Base Problem Estimation Method

Weak Acid/Base-Strong Base/Acid Titration Question

Course Reader pg. 156-157

MO Energy Diagrams for non-diamtomics

How to determine which orbital has less energy when drawing an MO Energy Diagram

Kc vs Kp vs Q [ENDORSED]

HOMO to LUMO Concept

Bonding vs. Anti-bonding

How to Fill Out a Molecular Orbital Energy Level Diagram

Lewis Structure Octet Rule Exceptions

General Rules on Writing e- Configurations [ENDORSED]

Rydberg Equation, Variations, and which n value to put first.

Re: Atomic Radius

Re: Threshold Energy Question

Re: Sig fig with constants

Re: Wavelike Properties? [ENDORSED]

Re: Dykstra Hall Study Group (Fall 2016)

Wave-Particle Duality and Equations Used

Re: Dykstra Hall Study Group (Fall 2016)

Re: Dykstra Hall Study Group (Fall 2016)

Dykstra Hall Study Group (Fall 2016)