Search found 32 matches
- Sat Mar 18, 2017 10:28 pm
- Forum: *Alcohols
- Topic: Final 2015 - 9B
- Replies: 2
- Views: 1422
Re: Final 2015 - 9B
The alcohol at the end of the propane is what is important here. So you will name it at the end.
- Sat Mar 18, 2017 9:37 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Number 5B from 2015 Final
- Replies: 2
- Views: 561
Number 5B from 2015 Final
"A standard electrochemical cell is made by placing a silver electrode into a 1.0 M Ag+ solution and a cadmium electrode into a 1.0 M Cd2+ solution. What is the redox reaction and what is the maximum potential, Ecell, produced by this cell?" How do I know which one is being oxidized and wh...
- Mon Mar 13, 2017 8:22 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Saying Thank You to Dr. Lavelle
- Replies: 490
- Views: 513517
Re: Saying Thank You to Dr. Lavelle
Dr. Lavelle, Thank you for being such an excellent instructor for Chem 14a as well as Chem 14b. Your hard work does not go unnoticed; the sheer amount of resources you give to your students is incredible. You truly want us all to succeed, and I will forever be grateful for having you as my first sci...
- Thu Mar 09, 2017 1:36 am
- Forum: Administrative Questions and Class Announcements
- Topic: Quiz 3 Winter 2017
- Replies: 183
- Views: 29022
Re: Quiz 3 Winter 2017
So if we have say, for example, a 35/40 on quiz 1, a 37/40 on quiz 2, and then we get a 10/40 on quiz 3, what will happen is we will get a 37/40 on quiz 3 in the gradebook?
- Thu Mar 09, 2017 1:25 am
- Forum: Administrative Questions and Class Announcements
- Topic: Quiz 3 Winter 2017
- Replies: 183
- Views: 29022
Re: Quiz 3 Winter 2017
We still get to drop our lowest quiz score, right?
- Tue Feb 14, 2017 9:30 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: 2015 Midterm Q4&5 part D
- Replies: 3
- Views: 782
Re: 2015 Midterm Q4&5 part D
We have to do step 3 because it wants the entropy of vaporization of water at 298k, so we need to bring it back down to room temperature in order to do that because the first two steps just calculate it for boiling But wouldn't the vapor turn to water again at that point? Why don't we calculate the...
- Tue Feb 14, 2017 9:10 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: 2015 Midterm Q4&5 part D
- Replies: 3
- Views: 782
2015 Midterm Q4&5 part D
Why do we do step 3? Why do we have to account for the entropy of the water vapor cooling from 373 K back down to 298 K? I understand why you do steps 1 and 2, but why step 3?
- Mon Feb 13, 2017 5:28 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Faraday Constant
- Replies: 3
- Views: 770
Re: Faraday Constant
If you look at page 50 in the course reader, there are 3 mols of electrons, but the Faraday Constant is still 96485 C/mol e-.
- Mon Feb 13, 2017 5:28 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Faraday Constant
- Replies: 3
- Views: 770
Re: Faraday Constant
I believe it is always the same constant.
- Sun Feb 12, 2017 11:07 pm
- Forum: Method of Initial Rates (To Determine n and k)
- Topic: reaction order
- Replies: 3
- Views: 856
Re: reaction order
This video may also be helpful to you https://www.khanacademy.org/science/che ... tion-order
- Sun Feb 12, 2017 11:07 pm
- Forum: Method of Initial Rates (To Determine n and k)
- Topic: reaction order
- Replies: 3
- Views: 856
Re: reaction order
You can do various plots and if it is a straight line, you can determine what order the rxn is. For example, for zero-order reactions, if you plot [A] vs. time, it should be a straight negative line.
- Fri Feb 10, 2017 12:44 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2999604
Re: Post All Chemistry Jokes Here
What is H204?
Drinking, cleaning your dishes, taking a shower, etc.
Drinking, cleaning your dishes, taking a shower, etc.
- Mon Jan 30, 2017 5:05 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: HW 8.49
- Replies: 1
- Views: 2232
HW 8.49
How do you find the temperature of the system? I understand everything else.
- Sat Jan 28, 2017 4:35 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Change in entropy= q/T [ENDORSED]
- Replies: 3
- Views: 733
Re: Change in entropy= q/T [ENDORSED]
As T gets larger, the 'change in entropy' will become smaller. As you divide by a bigger number, the answer becomes smaller.
- Mon Jan 16, 2017 2:40 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2999604
Re: Post All Chemistry Jokes Here
Did you know that you can cool yourself to -273.15˚C and still be 0k?
- Thu Jan 12, 2017 3:56 pm
- Forum: Phase Changes & Related Calculations
- Topic: Sublimiation
- Replies: 6
- Views: 1381
Re: Sublimiation
No, that would be like saying when water turns into ice it's called melting. I believe it is called deposition.
- Mon Nov 28, 2016 4:35 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2999604
Re: Post All Chemistry Jokes Here
My teacher threw some sodium chloride at me.
That's a salt!
That's a salt!
- Mon Nov 21, 2016 1:37 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Pressure/Expansion effect on products and reactants
- Replies: 2
- Views: 641
Re: Pressure/Expansion effect on products and reactants
An increase in expansion is increasing the volume, so the reverse action will occur (concentration moves from lower moles equation -> higher moles side of equation)
- Fri Nov 18, 2016 1:24 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: coordination number [ENDORSED]
- Replies: 3
- Views: 898
Re: coordination number [ENDORSED]
Bonds with the central transition metal
- Mon Nov 14, 2016 8:20 pm
- Forum: Ideal Gases
- Topic: ΔH?
- Replies: 2
- Views: 697
Re: ΔH?
Positive value means endothermic. Negative value means exothermic.
- Mon Nov 14, 2016 2:09 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Ligand Names
- Replies: 3
- Views: 658
Re: Ligand Names
I doubt Dr. Lavelle would do something like that.
- Mon Oct 24, 2016 10:56 pm
- Forum: Ionic & Covalent Bonds
- Topic: Chemical Formulas
- Replies: 1
- Views: 438
Re: Chemical Formulas
I read a post by Dr. Lavelle earlier but I can't find it right now.
It said that formulas for uncommon molecules will be given.
It said that formulas for uncommon molecules will be given.
- Mon Oct 24, 2016 10:51 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: e- configuration regarding 3d and 4s orbitals
- Replies: 2
- Views: 488
Re: e- configuration regarding 3d and 4s orbitals
3d.
for example here is Scandium's electron configuration:
[Ar] 3d1 4s2 .
for example here is Scandium's electron configuration:
[Ar] 3d1 4s2 .
- Mon Oct 24, 2016 10:50 pm
- Forum: Trends in The Periodic Table
- Topic: Periods 15 and 14 relationship
- Replies: 2
- Views: 653
Re: Periods 15 and 14 relationship
I think you meant Groups 15 and 14.
From what I have seen online, there is no real pattern or trend for groups 15 and 14. One thing for sure though is that Nitrogen has a very low electron affinity value.
From what I have seen online, there is no real pattern or trend for groups 15 and 14. One thing for sure though is that Nitrogen has a very low electron affinity value.
- Mon Oct 24, 2016 10:47 pm
- Forum: Ionic & Covalent Bonds
- Topic: Formal Charge
- Replies: 1
- Views: 389
Re: Formal Charge
Ionic bonds are usually not written with dashes to show bonds like how covalent bonds are represented. The ions should have their own respective charges in the corner in the case of ionic bonds.
- Mon Oct 24, 2016 10:45 pm
- Forum: Lewis Structures
- Topic: Lewis Structures with the noble gases
- Replies: 1
- Views: 1644
Re: Lewis Structures with the noble gases
Any element before phosphorus cannot expand past an octet. This means elements beyond it (including phosphorus) are able to break this ' octet rule' .
- Mon Oct 24, 2016 10:43 pm
- Forum: Resonance Structures
- Topic: Resonance vs. Lewis Structure?
- Replies: 9
- Views: 2253
Re: Resonance vs. Lewis Structure?
It should ask for resonance structures in the question if that is what they are looking for. If it just asks to draw THE lewis structure, like in question 101a in chapter 3, there is only one correct structure.
- Mon Oct 24, 2016 2:21 pm
- Forum: Ionic & Covalent Bonds
- Topic: Stronger bonds
- Replies: 3
- Views: 1866
Re: Stronger bonds
The bond length and the type of bond tell you a lot about the strength of the bond.
Ionic > covalent in terms of strength in most cases.
triple bond > double bond > single bonds in most cases. Triple bonds are shortest, single are longest.
Ionic > covalent in terms of strength in most cases.
triple bond > double bond > single bonds in most cases. Triple bonds are shortest, single are longest.
- Mon Oct 17, 2016 12:36 am
- Forum: Ionic & Covalent Bonds
- Topic: Metallic bonds, Lewis Structures
- Replies: 2
- Views: 1036
Re: Metallic bonds, Lewis Structures
I'm not sure about the first question, but to answer your second question, the order doesn't matter. Just as long as you write your structure accurately and have the correct amount of electrons in it, you should be fine.
- Mon Oct 10, 2016 5:22 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: HW 1.15
- Replies: 3
- Views: 700
Re: HW 1.15
How would we solve this problem using the formula we used in class En=-(hR/n^2)? He never went over this formula in class so won't you get the same answer using the other formula as well? The formula in the reply above is the same as the formula we used in class (En = -(hR/n^2)). But the question i...
- Thu Oct 06, 2016 9:56 pm
- Forum: Empirical & Molecular Formulas
- Topic: Nomenclature?
- Replies: 1
- Views: 552
Nomenclature?
Will we have to know nomenclature (names of chemicals and formulas for chemicals) for the quizzes/midterms/finals? If so, which ones should we study? As many as we can? Thanks for the help.
- Tue Sep 27, 2016 11:07 am
- Forum: Student Social/Study Group
- Topic: Rieber Hall 14A Study Group (Fall 2016)
- Replies: 49
- Views: 9836
Re: Rieber Hall 14A Study Group (Fall 2016)
Hi, I live on the fourth floor and I'd like to join! Keep me posted on meeting times and if you guys decide to make a group me!