Search found 21 matches

Tue Mar 08, 2016 9:08 pm
Forum: *Cyclopentanes
Topic: final 2007 6b
Replies: 6
Views: 2418

Re: final 2007 6b

thanks!
Fri Mar 04, 2016 10:00 am
Forum: *Alkanes
Topic: Quiz 3 Preparation
Replies: 34
Views: 11648

Re: Quiz 3 Preparation

thanks!
Thu Feb 25, 2016 12:25 pm
Forum: Kinetics vs. Thermodynamics Controlling a Reaction
Topic: half lives
Replies: 4
Views: 11321

Re: half lives

thanks!
Tue Feb 16, 2016 5:29 pm
Forum: General Rate Laws
Topic: Quiz 2 Prep Winter 2014 Activation Energy
Replies: 1
Views: 330

Quiz 2 Prep Winter 2014 Activation Energy

Quiz 2 Prep Winter 2014 #10 asks for the activation energy for the reaction.

I am confused as to which formula to use and what values to put in it. I thought we need to use ln (k'/k)= (Ea/R)(T'-T/T'T); however, I am not sure of what values to plug in for T and T'.

Thanks
Tue Feb 16, 2016 3:35 pm
Forum: Administrative Questions and Class Announcements
Topic: Up to what problem should we work in the textbook?
Replies: 4
Views: 561

Re: Up to what problem should we work in the textbook?

I stopped at question 15.65 because the questions started to talk about catalysis which we haven't covered yet.
Thu Feb 11, 2016 12:32 pm
Forum: Kinetics vs. Thermodynamics Controlling a Reaction
Topic: Kinetics
Replies: 2
Views: 610

Re: Kinetics

Thank you!
Tue Feb 02, 2016 9:15 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Simplifying Ecell
Replies: 1
Views: 334

Simplifying Ecell

If T is a different value does (2.303RT)/(F) still equal to .059 V? Thanks!
Mon Jan 25, 2016 3:14 pm
Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
Topic: Work Done on System or By System
Replies: 2
Views: 12648

Work Done on System or By System

Hello, I was wondering how you know if work is being done by the system or on the system and how to determine it. Thank you!
Wed Jan 20, 2016 4:38 pm
Forum: Phase Changes & Related Calculations
Topic: Ch 8.10 Topics
Replies: 2
Views: 398

Ch 8.10 Topics

Chapter 8.10 talks about the equipartition theorem and rotational energy. Do we need to know these terms for this course? Thanks!
Fri Jan 15, 2016 12:55 pm
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: Entropy as a property
Replies: 1
Views: 383

Re: Entropy as a property

Entropy is an extensive property labeled with S; however, specific entropy is an intensive property labeled with s. Entropy is extensive because its amount changes based on the quantity of matter in the system. An example would be that it takes more heat to melt a bucket of ice than it does to melt ...
Wed Jan 06, 2016 9:16 pm
Forum: Phase Changes & Related Calculations
Topic: Hess's Law
Replies: 8
Views: 1059

Re: Hess's Law

I believe today in lecture Dr. Lavelle said that you could use any of the methods and get the same result, but we have only gone through two of the three ways.
Mon Nov 30, 2015 8:56 pm
Forum: Conjugate Acids & Bases
Topic: Weak Acid and Weak Base
Replies: 1
Views: 373

Weak Acid and Weak Base

What would happen if you had a weak acid and weak base reacting? Is this even plausible? Thanks!
Mon Nov 23, 2015 1:32 pm
Forum: Naming
Topic: Using the word ion
Replies: 2
Views: 553

Using the word ion

I was wondering how you know whether or not to use the word "ion" when naming a chemical compound. Does saying "ion" at the end of the name mean that it has a negative charge? Or does it not affect the name in any way? Thanks!
Mon Nov 16, 2015 9:54 pm
Forum: Naming
Topic: complex has positive charge
Replies: 1
Views: 399

Re: complex has positive charge

For complexes with a positive charge, you usually add a Roman numeral in parenthesis after the element. An example would be (Co(en)2(CN)Cl)Cl. The name of this compound would be chlorocyanobisethylenediaminecobalt(II) chloride.

Hope this helped!
Wed Nov 11, 2015 5:24 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Compression and photosynthesis. 11.115 hmwk
Replies: 4
Views: 635

Re: Compression and photosynthesis. 11.115 hmwk

Change in pressure does not change K. In this case, even though more pressure may be on the reactants, the reaction will eventually reach equilibrium again and balance out. Refer to page 129 in the course reader.
Mon Nov 02, 2015 12:12 pm
Forum: Einstein Equation
Topic: 2010 Midterm Review Q4 Mass of Chromium
Replies: 1
Views: 616

2010 Midterm Review Q4 Mass of Chromium

Q4. The work function for chromium metal is 4.37eV. What wavelength of radiation must be used to eject electrons with a velocity of 1.5x10^3 kms-1? In the answer provided to this question, they use the formula Ek=(1/2)mv^2 which makes sense. The next step is Ek=(1/2) (9.10939x10^-31 kg)(1.5x10^6ms-1...
Tue Oct 27, 2015 6:42 pm
Forum: Formal Charge and Oxidation Numbers
Topic: Formal charge and resonance structures
Replies: 2
Views: 593

Re: Formal charge and resonance structures

Calculating a formal charge is not necessarily mandatory in order to determine if there is resonance or a better Lewis structure for a compound; however, it is an extremely accurate and efficient way to determine what the best Lewis structure is. The formal charge of a compound must be equal to the ...
Fri Oct 23, 2015 3:59 pm
Forum: Hybridization
Topic: Unhybridized p orbitals
Replies: 2
Views: 1354

Re: Unhybridized p orbitals

The hybridization of a molecule is not dependent upon the number of valence electrons carbon has. The valence electrons are necessary in order to form the Lewis structure of ethene; however, when determining hybridization, valence electrons do not influence the electron density because you have alre...
Fri Oct 23, 2015 3:46 pm
Forum: Resonance Structures
Topic: Resonance
Replies: 2
Views: 583

Re: Resonance

Resonance structures are used when one Lewis structure for a single molecule cannot fully describe the bonding that takes place between neighboring atoms relative to the empirical data for the actual bond lengths between those atoms. More info on this: http://chemwiki.ucdavis.edu/Theoretical_Chemist...
Thu Oct 08, 2015 10:01 am
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Electron Configuration Sequence
Replies: 1
Views: 405

Electron Configuration Sequence

When writing an electron configuration for Vanadium (or any other element in the d-block), why does the 3d come before the 4s? For Vanadium, why is it (Ne)3s^2 3p^6 3d^3 4s^2 and not (Ne)3s^2 3p^6 4s^2 4d^3? I just don't understand why the number associated with the d series is always one less than ...
Fri Oct 02, 2015 3:05 pm
Forum: Significant Figures
Topic: Use of Significant Figures with Constants
Replies: 3
Views: 10415

Re: Use of Significant Figures with Constants

When determining the amount of significant figures to use in a problem, be sure to always use the amount of significant figures in the variable given to you in the question. For example, if the equation tells you that the velocity is 2.4 x 10^5 and the constant is the speed of light at 2.999999 x 10...