Search found 13 matches

by Alyssa McLeod 3E
Sun Mar 12, 2017 9:21 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Transition States
Replies: 2
Views: 356

Transition States

Could someone explain the difference between transition states and intermediates? Thanks!
by Alyssa McLeod 3E
Sun Mar 05, 2017 7:21 pm
Forum: *Cycloalkanes
Topic: Prefix in Naming
Replies: 1
Views: 333

Prefix in Naming

I am still unsure when to use a prefix in naming an organic compound, like we did with "tert" in 1-tert-Butyl-4-Methylcyclohexane. This prefix did not seem to come up in any other examples in class, and I'm wondering what made this example unique.
by Alyssa McLeod 3E
Sun Feb 19, 2017 7:20 pm
Forum: Kinetics vs. Thermodynamics Controlling a Reaction
Topic: Multi Step Reaction
Replies: 2
Views: 350

Multi Step Reaction

In a multistep reaction, how do you determine which step is the slow, or limiting, step? That is, how do you know which reactants to ignore while setting up a rate equation?
by Alyssa McLeod 3E
Sun Feb 12, 2017 9:58 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Concentration Powered Battery
Replies: 1
Views: 291

Concentration Powered Battery

In the example in class where the battery was powered by a concentration gradient, why was E0 0? Was it because the reactants and products were the same on both side?
by Alyssa McLeod 3E
Sun Feb 05, 2017 6:22 pm
Forum: Balancing Redox Reactions
Topic: Oxidation and Reduction
Replies: 3
Views: 446

Oxidation and Reduction

In the molecule is Cr2O7(2-), is the charge on the Cr 12+ (since the charge on the O7 totals 14-), or 6+ since there are two chromium atoms? If it's the latter, does that mean the charge on a single oxygen atom is always 2-?
by Alyssa McLeod 3E
Sun Jan 29, 2017 3:14 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Bond Enthalpies
Replies: 1
Views: 272

Bond Enthalpies

When calculating enthalpy of a reaction with bond enthalpies, when is data other than the given bond enthalpies relevant? For example, for chapter 8, hw problem 67, why was the standard enthalpy of sublimation relevant? In using bond enthalpies, do we always have to take into account state changes a...
by Alyssa McLeod 3E
Sun Jan 22, 2017 12:42 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: HW 8.47
Replies: 2
Views: 362

HW 8.47

For a certain reaction at constant pressure, \Delta U=-15kJ , and 35kJ of expansion work is done by the system. What is \Delta U for this reaction? I got the correct answer by using the formula \Delta U=\Delta H+w but when I checked my answer via an old post here on chemistry community, someone made...
by Alyssa McLeod 3E
Sun Jan 15, 2017 4:21 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Work Done by or on the System [ENDORSED]
Replies: 3
Views: 484

Work Done by or on the System [ENDORSED]

When using the first law of thermodynamics, how would one distinguish between work done *by* or *on* the system? If a piston compresses a gas, work is obviously done *on* the system, but what is an example of work being done *by* the system?
by Alyssa McLeod 3E
Tue Nov 15, 2016 11:05 am
Forum: Naming
Topic: Partial Pressure
Replies: 1
Views: 330

Partial Pressure

If the partial pressure of a reactant is decreased, what will happen to the partial pressure of a product when reestablishing equilibrium? Does it make a difference that the question asks for "partial pressure" instead of just "pressure?" That is, if I were to write out the equil...
by Alyssa McLeod 3E
Tue Oct 25, 2016 2:57 pm
Forum: Lewis Structures
Topic: Finding Hybrid Orbitals
Replies: 5
Views: 602

Re: Finding Hybrid Orbitals

Got it! Around the central atom only, yes? I think that was my error. So from there, I can calculate that ICl2- has 5e- pairs, which corresponds with the configuration sp3d. Why? Is that something I should memorize, or is there an efficient calculation I can do to go from electron pairs to a particu...
by Alyssa McLeod 3E
Sun Oct 23, 2016 1:11 pm
Forum: Lewis Structures
Topic: Finding Hybrid Orbitals
Replies: 5
Views: 602

Finding Hybrid Orbitals

One way to predict hybrid orbitals is to calculate the number of electron pairs. For H3O+ oxygen has 6 valence electrons, 3 hydrogens have three, minus one electron equals 8 electrons, or 4 pairs, which means the hybrid orbital is sp3. So, then, in Icl2- iodine has 7 valence electrons and 2 Chlorine...
by Alyssa McLeod 3E
Tue Oct 11, 2016 4:27 pm
Forum: DeBroglie Equation
Topic: Rydberg Constant
Replies: 1
Views: 326

Rydberg Constant

Many sources on the internet express the Rydberg Constant as 1.0973731.6 * 10^7 m-1, but it's in the workbook as 3.38984 * 10^15 Hz, which is the speed of light multiplied by the popular internet constant. So, if I use the R=3.38984 * 10^15 Hz, does the Rydberg equation then become c/\lambda=R(1/n_2...
by Alyssa McLeod 3E
Fri Oct 07, 2016 8:06 pm
Forum: Administrative Questions and Class Announcements
Topic: Quizes
Replies: 21
Views: 1684

Re: Quizes

I also have a question about the quiz. I understand that it will cover all the lecture material, but does that include the review that we were supposed to study from the modules before beginning the class?

Go to advanced search