Search found 25 matches
- Fri Mar 11, 2016 11:04 pm
- Forum: *Cycloalkenes
- Topic: Numbering
- Replies: 2
- Views: 849
Re: Numbering
It cannot be 1,2-dichlorocyclohexene because of the double bond. Naming it that way would actually result in an incorrect name of 1,2-dichlorohex-2-ene.
- Wed Mar 09, 2016 3:59 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Detailed Midterm Solutions
- Replies: 1
- Views: 523
Re: Detailed Midterm Solutions
The detailed midterm solutions are posted on the Chem14B class website
- Fri Mar 04, 2016 1:59 am
- Forum: *Nucleophiles
- Topic: Is CO2 a nucleophile or electrophile?
- Replies: 1
- Views: 12314
Re: Is CO2 a nucleophile or electrophile?
Carbon dioxide is an electrophile. If you draw out the Lewis structure for CO2, you can see that carbon is central and is bound to two oxygen atoms. The electronegativity of oxygen gives carbon a partial positive charge, making carbon dioxide an electrophile (Carbon is electron deficient).
- Thu Feb 25, 2016 10:37 am
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2956161
- Thu Feb 18, 2016 1:59 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Midterm distribution
- Replies: 3
- Views: 847
Re: Midterm distribution
When will the midterm solutions be available?
- Thu Feb 11, 2016 6:40 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2956161
- Tue Feb 02, 2016 8:44 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: Standard Reduction Potential as Intensive Property
- Replies: 2
- Views: 2467
Re: Standard Reduction Potential as Intensive Property
Also, with regard to density, it is an intensive property since it is independent of the amount/size of the material/sample. Density is mass (extensive property) divided by volume (extensive property). An extensive property divided by an extensive property is an intensive property. State properties ...
- Tue Feb 02, 2016 8:33 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: Standard Reduction Potential as Intensive Property
- Replies: 2
- Views: 2467
Re: Standard Reduction Potential as Intensive Property
Standard reduction potential is an intensive property. You might multiply a half reaction by 2 to balance the electrons, but the standard reduction potential is constant and does not need to be multiplied by 2 (unlike bond enthalpies).
- Fri Jan 29, 2016 5:09 pm
- Forum: Balancing Redox Reactions
- Topic: Oxidation state
- Replies: 1
- Views: 512
Oxidation state
Are oxidation state and oxidation number interchangeable terms, or is there any difference between them?
- Thu Jan 21, 2016 6:19 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Picking up the final
- Replies: 1
- Views: 795
Re: Picking up the final
You pick them up at 4006 Young Hall. Finals should be available this week, but I'm not sure what their hours are, sorry.
- Wed Jan 13, 2016 6:45 pm
- Forum: Calculating Work of Expansion
- Topic: Reversible and Irreversible
- Replies: 3
- Views: 858
Re: Reversible and Irreversible
I think we have to know that a reversible process is a system at equilibrium (infinitely small changes in a variable can reverse the process) and that maximum work is achieved in a reversible process.
- Thu Jan 07, 2016 8:05 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Equipartition theorem
- Replies: 1
- Views: 574
Equipartition theorem
Just out of curiosity, how high does the temperature have to be to use the equipartition theorem in calculations of vibrational motion? Thank you in advance!
- Thu Dec 03, 2015 10:31 am
- Forum: *Making Buffers & Calculating Buffer pH (Henderson-Hasselbalch Equation)
- Topic: Henderson-Hasselbach equation
- Replies: 1
- Views: 999
Henderson-Hasselbach equation
Are we only allowed to use the Henderson-Hasselbach equation for questions involving buffers, thereby using (R)ICE boxes for every other calculation of pH?
- Tue Nov 24, 2015 12:22 pm
- Forum: Photoelectric Effect
- Topic: equations for the photoelectric effect
- Replies: 1
- Views: 691
equations for the photoelectric effect
On Question 3b of the midterm, the question asks for the energy required to remove the electron from the metal surface. I calculated the work function (energy of the photon - kinetic energy of the electron). Why is the answer (1.66 x 10^-17 J) equivalent to only the energy of the photon if informati...
- Wed Nov 18, 2015 1:24 pm
- Forum: Ideal Gases
- Topic: When to use atm or bar
- Replies: 2
- Views: 825
When to use atm or bar
When calculating Kp, does it matter whether we use atm or bar? In the Fall 2014 Quiz 3 Preparation Q8, I understand that the answer should be given in atm since that is the unit provided in the question, but for Q10, is the answer in atm because we use the ideal gas law? Also regarding Q10, why do t...
- Sat Nov 14, 2015 6:53 pm
- Forum: Naming
- Topic: Bisoxalato vs. Dioxalato
- Replies: 1
- Views: 2925
Re: Bisoxalato vs. Dioxalato
If the ligand is polydentate, you use the prefixes bis-, tris-, tetrakis-, pentakis, etc. Oxalate is a bidentate ligand; therefore, you use bisoxalato, not dioxalato.
- Sat Nov 14, 2015 6:48 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Polydentate Ligands
- Replies: 1
- Views: 539
Re: Polydentate Ligands
Yes, if a ligand is polydentate and there is more than one in a coordination compound, you use the prefixes bis-, tris-, tetrakis-, pentakis-, etc.
- Sun Nov 08, 2015 8:48 pm
- Forum: Naming
- Topic: Naming Coordination Compounds
- Replies: 1
- Views: 525
Re: Naming Coordination Compounds
I think you can write aqua as either H2O or OH2 when naming coordination compounds. Some people write aqua as OH2 to emphasize the order of bonding since oxygen (not hydrogen) is the one binding to other elements, but writing H2O shouldn't be wrong either.
- Fri Oct 30, 2015 9:20 am
- Forum: Lewis Structures
- Topic: Lewis Sturcture of (CH3)2Be
- Replies: 1
- Views: 2906
Re: Lewis Sturcture of (CH3)2Be
You would draw (CH3)2Be as a linear molecule. Beryllium would be your central atom, and it forms two bonds, one to each Carbon of the CH3. Each Carbon is thus bonded to Beryllium and to 3 hydrogens so it achieves octet. There are a total of 16 valence electrons ( C: 4*2=8, Be:2, H: 1*6=6.......... 8...
- Fri Oct 30, 2015 8:53 am
- Forum: Significant Figures
- Topic: How many significant figures does this question require?
- Replies: 1
- Views: 716
Re: How many significant figures does this question require?
I think you would use one significant digit because that is the least precise measurement given in the question. In general, I believe you evaluate the number of significant figures before you convert units accordingly so I would decide based on the numbers provided in the problem. The answer using ...
- Sat Oct 17, 2015 12:43 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Aufbau Princple
- Replies: 2
- Views: 646
Re: Aufbau Princple
Silver is in the same group as Copper, which is an exception to the Aufbau Principle (the building-up principle), the other being Chromium. In these two cases, half full d^5 and full d^10 subshells have lower energy. For Chromium, the electron configuration would be [Ar] 3d^5 4s^1 instead of [Ar] 3d...
- Sun Oct 11, 2015 12:17 am
- Forum: Significant Figures
- Topic: All students read this sig fig post [ENDORSED]
- Replies: 170
- Views: 33489
Re: All students read this sig fig post [ENDORSED]
The purpose of using significant figures is to make sure that the answer you calculated isn't more precise than the number(s) you started with. If one rounds off numbers too soon, errors in calculations may occur, and significant margins of error can affect data collection. Also, the number of signi...
- Thu Oct 08, 2015 12:34 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2956161
Re: Chemistry Jokes
What do you call Iron blowing in the wind?
Febreeze
Febreeze
- Wed Sep 30, 2015 10:10 pm
- Forum: Significant Figures
- Topic: All students read this sig fig post [ENDORSED]
- Replies: 170
- Views: 33489
Re: All students read this sig fig post [ENDORSED]
If there is a multistep problem, do we maintain four significant figures per step, even for the following step? For example, if part A requires an answer with only four significant figures (example: 1.178), and part B uses that answer to solve for another variable, should we use 1.178 or the extende...
- Fri Sep 25, 2015 8:34 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Homework
- Replies: 5
- Views: 1065
Re: Homework
Doing all the reading before jumping into the practice problems does take some time, but even though there's no way to truly check if we use the textbook chapters as a resource, I think that reading the assigned chapters could only help us understand the conceptual side of the course material more f...