Search found 27 matches
- Fri Mar 17, 2017 1:56 am
- Forum: *Alcohols
- Topic: Double bonds and functional groups
- Replies: 1
- Views: 1317
Double bonds and functional groups
I know the professor has probably answered this multiple times, but just to reiterate: We do NOT have to know how to name of a compound that contains both a functional group AND a separate double bond such as number 40 in chapter 2 which asks for the name of an alcohol that also contains a double bo...
- Thu Mar 16, 2017 11:22 pm
- Forum: *Cyclopentanes
- Topic: Difference in Strains
- Replies: 1
- Views: 1309
Difference in Strains
I still don't quite understand the different between steric, angle, and torsional strain?
- Mon Mar 13, 2017 1:26 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: A in the Arrhenius equation
- Replies: 2
- Views: 721
A in the Arrhenius equation
I'm still confused as to what A is in the Arrhenius equation?
We never used it in our homework or quiz. Is there a time we will use it?
Is it constant for all equations?
We never used it in our homework or quiz. Is there a time we will use it?
Is it constant for all equations?
- Sun Mar 05, 2017 6:03 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Quiz 3 Winter 2017
- Replies: 183
- Views: 29753
Re: Quiz 3 Winter 2017
For the first question, how do you know it is 4- isopropyldecane? I thought that it was just 4-propyldecane
- Sun Feb 26, 2017 5:09 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Pre-equilibrium
- Replies: 3
- Views: 879
Pre-equilibrium
for the pre-equilibrium approach are you always trying to rewrite the rate law of the fast reaction in terms of the slow reaction to find the overall reaction?
- Sun Feb 26, 2017 5:03 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3622559
Re: Post All Chemistry Jokes Here
Why did the white bear dissolve in water?
Because it was polar!
Because it was polar!
- Sun Feb 19, 2017 2:36 am
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3622559
Re: Post All Chemistry Jokes Here
Q: Why do chemists like nitrates so much?
A: They're cheaper than day rates.
A: They're cheaper than day rates.
- Sat Feb 11, 2017 8:05 pm
- 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 2014 Winter Q5A
- Replies: 2
- Views: 693
Midterm 2014 Winter Q5A
consider a nano-crystal formed from 8 identical molecules that can have three possible equal energy orientations. calculate the residual (minimum) entropy for this system. I keep getting 1.21 x 10^-22 However the answer is 1.15x10^-22 I can't seem to get the same answer even though I'm fairly certai...
- Sat Feb 11, 2017 6:20 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: Midterm 2013 Q7
- Replies: 1
- Views: 415
Midterm 2013 Q7
The question asks to calculate K for a redox reaction at 298 K. And it says you can solve it two ways: However when I try and solve it using Delta G = -RTlnK I keep getting 1.35x10^-72 (whereas the answer is 9.2x10^-72) Known: When solving delta G= 4.1x10^5 J/mol. Could someone please help me out? I...
- Thu Feb 09, 2017 11:49 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: 14.35
- Replies: 1
- Views: 504
14.35
Hi! 14.35: determine the equilibrium constants for the following reaction: Mn (s) + Ti^2+ (aq) --> Mn^2+ (aq) + Ti (s) I don't understand why when you solve for the cell potential it is negative?? I thought you always make it so that the cell potential is positive, even if that means reversing the c...
- Wed Feb 08, 2017 4:43 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Cell diagram electrode
- Replies: 1
- Views: 317
Cell diagram electrode
Hi! I understand that when half reactions don't have a solid that it needs an electrode (such as Pt). However I was confused as to why question 14.13 needs an electrode for I: Ce 4+ (aq) + I- (aq) --> I2(s) + Ce3+(aq) I understand that Ce needs an electronde because both are aqueous. But I thought s...
- Sat Feb 04, 2017 1:14 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Units of entropy [ENDORSED]
- Replies: 3
- Views: 852
Units of entropy [ENDORSED]
I had always thought that the units for entropy was: joules/moles x kelvin
But is it possible for it to be just:
joules/kelvin?
But is it possible for it to be just:
joules/kelvin?
- Tue Jan 24, 2017 9:18 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Gibbs Free Energy: Spontaneous versus Unstable?
- Replies: 2
- Views: 869
Gibbs Free Energy: Spontaneous versus Unstable?
In problem number 9.63 in the textbook it asks: Determine which of the following compounds are stable with respect to decomposition into their elements under standard conditions at 25 degrees C. The answer was that those with negative free energies were stable. However my understanding was that bein...
- Sat Jan 21, 2017 4:04 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Hess's Law
- Replies: 1
- Views: 520
Hess's Law
How come when using Hess's law you usually don't include elements in their natural state (such as H2), but when it is combustion you do include it in calculating the enthalpy?
Thanks in advance!
Thanks in advance!
- Tue Jan 10, 2017 4:23 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Bruincast posting time
- Replies: 2
- Views: 634
Bruincast posting time
When is the earliest that we can view a bruincast? Is it posted the day of, the following day? Because a couple times it didn't seem to be on the bruincast website.
- Wed Nov 30, 2016 8:08 pm
- Forum: *Making Buffers & Calculating Buffer pH (Henderson-Hasselbalch Equation)
- Topic: Henderson-Hasselbalch pOH
- Replies: 1
- Views: 568
Henderson-Hasselbalch pOH
Is there a way to use Henderson-hasselbalch with pOH or pKb? or do you first have to convert everything to pH and pKa and then use the equation?
- Sun Nov 20, 2016 4:36 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: When can you disregard X? [ENDORSED]
- Replies: 1
- Views: 392
When can you disregard X? [ENDORSED]
When using an ice chart, and solving for X, when is it appropriate to disregard X in the difference between the initial molar concentration and the change in molar concentration? Did Dr. lavelle give a specific number for K? Some number we can use in reference (as in when K is smaller than some numb...
- Sun Nov 20, 2016 4:18 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: K=1 [ENDORSED]
- Replies: 2
- Views: 579
K=1 [ENDORSED]
How come K=1 is rare?
- Thu Nov 10, 2016 4:17 pm
- Forum: Naming
- Topic: When does the transition metal change to -ide?
- Replies: 3
- Views: 1002
When does the transition metal change to -ide?
When naming, when does the transition metal ending change to -ide? and is the transition metal always named at the end when written out, but in the written in the beginning when written with chemical symbols?
- Tue Nov 01, 2016 10:11 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: T-Shaped?
- Replies: 1
- Views: 532
T-Shaped?
AX3E2 (3 bonds with 2 lone pairs) is considered T-shaped. However I would have thought it would be trigonal planar because the lone pairs would want to get as far away from one another as possible (such as at a 180 degree angle with the 3 bonds in the middle in a triangle shape with 120 degree angle...
- Sun Oct 30, 2016 12:29 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: What is Angular? And what is T-shaped?
- Replies: 2
- Views: 882
What is Angular? And what is T-shaped?
Is Angular the same shape as bent?
And what is T-shaped?
And what is T-shaped?
- Wed Oct 19, 2016 10:59 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: What are considered thhe e- in the outer shell?
- Replies: 3
- Views: 913
What are considered thhe e- in the outer shell?
Hi there! I'm confused on what we should consider to be the electrons in the outer shell? For example I know that for 1s^2 2s^2 2p^6, the number of electrons in the outer shell would be 8 because you would look at the number of electrons in the highest energy level (or valence electrons). But in tha...
- Wed Oct 19, 2016 10:50 pm
- Forum: Lewis Structures
- Topic: Question 3.67 part B?
- Replies: 2
- Views: 590
Question 3.67 part B?
Hi there! I am confused on the answer to question 3.67 in the textbook which asks: "in each of these compounds, an atom violates the octet rule. Identify the atom and explain the deviation from the octet rule? B) ClO2" I would have thought that the answer would have been chlorine in the mi...
- Tue Oct 11, 2016 4:44 pm
- Forum: Significant Figures
- Topic: Sig fig with constants
- Replies: 2
- Views: 924
Sig fig with constants
When you are given only constants to work with in a problem, how many sig figs should you use? such as for Rydberg's equation, if all you are given are n=1, and n=3, how many sig figs are you supposed to have in your answer? should you round the constants (such as plank's constant) to a more reasona...
- Sat Oct 08, 2016 5:04 pm
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: Heisenberg Uncertainty-Which numbers to use? Sig Figs? [ENDORSED]
- Replies: 1
- Views: 481
Heisenberg Uncertainty-Which numbers to use? Sig Figs? [ENDORSED]
If a problem tells you (just making up an example) that something with the mass of 10 kg is going at the speed of 3.50 m/s plus or minus .4 m/s, which number would you use to solve the for the momentum? Would delta x be .4 + .4= .8 m/s? And if so, does that mean that in your answer you would only ha...
- Wed Oct 05, 2016 12:38 am
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Atomic spectra
- Replies: 1
- Views: 353
Atomic spectra
When a high energy electron drop to a lower energy level how come it doesn't always drop to the lowest energy level (n=1)? What stops it from releasing all of its energy?
- Thu Sep 29, 2016 5:27 pm
- Forum: Photoelectric Effect
- Topic: Photoelectric effect- how is it detected?
- Replies: 1
- Views: 489
Photoelectric effect- how is it detected?
When the photoelectric effect was conducted, or is conducted, how are the electrons (the ones being emitted) being detected or measured? Are they being detected individually? All together? By the amount of kinetic energy they have? And is their any way that the electrons can be detected visibly (as ...