Search found 26 matches
- Sun Mar 12, 2017 7:59 pm
- Forum: *Constitutional and Geometric Isomers (cis, Z and trans, E)
- Topic: Geometric isomers as line structures
- Replies: 4
- Views: 891
Re: Geometric isomers as line structures
Also, remember that Z groups are on zee zame zide!!!
- Sun Mar 05, 2017 4:58 pm
- Forum: *Alkanes
- Topic: sec and tert
- Replies: 2
- Views: 610
sec and tert
Are the prefixes 'sec' and 'tert' only for the butyl substituent? I don't know when to use them
- Sun Mar 05, 2017 4:27 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Quiz 3 Winter 2017
- Replies: 183
- Views: 29026
Re: Quiz 3 Winter 2017
In class, we never discussed "electrophilic aromatic substitution," but it is in section 4.2 of the organic chem textbook. Are we expected to know this for quiz 3 and for the final?
- Sun Feb 26, 2017 11:38 pm
- Forum: *Nucleophiles
- Topic: strength of nucleophiles vs basicity
- Replies: 2
- Views: 533
strength of nucleophiles vs basicity
What is the difference between the trend in how basic something is and how nucleophilic it is?
- Sun Feb 19, 2017 9:44 pm
- Forum: General Rate Laws
- Topic: Elementary Rate Laws
- Replies: 1
- Views: 505
Elementary Rate Laws
Why can you take the coefficient before a molecule and include it in the exponent in the rate law for elementary rxns, but you can't do this for first order or second order rxns?
- Sun Feb 12, 2017 7:39 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Order of ions in cell diagram
- Replies: 1
- Views: 443
Order of ions in cell diagram
I know that for cell diagram short notation, you write the anode on the left and the cathode on the right. But, does it matter in which what order you write the ions/elements.
- Sun Feb 05, 2017 9:11 pm
- Forum: Balancing Redox Reactions
- Topic: Balancing Redox Reactions: Basic vs Acidic
- Replies: 1
- Views: 505
Balancing Redox Reactions: Basic vs Acidic
I just started the homework problems for Ch 14. I am really confused. Do we have to know how to balance redox reactions that take place in acidic and basic solutions? If so, do you have any tips?
- Sun Jan 29, 2017 8:25 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: stability and spontaneity
- Replies: 1
- Views: 578
stability and spontaneity
can someone please explain why it is more stable if delta G is negative/spontaneous?
- Sun Jan 29, 2017 2:46 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Quiz 1 Study Group
- Replies: 1
- Views: 421
Quiz 1 Study Group
Hi. If you live in Hedrick Summit, would you like to meet up and study for our first chem quiz Tuesday night?
- Fri Jan 20, 2017 6:41 pm
- Forum: Phase Changes & Related Calculations
- Topic: irreversible vs reversible expansions
- Replies: 2
- Views: 612
irreversible vs reversible expansions
Can someone please explain the difference between these two? I am having a hard time visualizing it. Irreversible has a constant pressure, and reversible does not? Correct? I also never know what formula to use for work.
- Sat Jan 14, 2017 1:09 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Measuring Heat Transfer (extensive vs intensive)
- Replies: 2
- Views: 583
Measuring Heat Transfer (extensive vs intensive)
In lecture on Friday, I was confused about the difference between extensive property and intensive property. Can someone please elaborate?
- Sat Jan 14, 2017 1:04 pm
- Forum: Phase Changes & Related Calculations
- Topic: phase changes [ENDORSED]
- Replies: 3
- Views: 959
Re: phase changes [ENDORSED]
Correct. In order for a solid to go to a liquid, it must absorb heat, so it is endothermic and positive delta H. When a liquid goes to a solid, it must release heat, so it is exothermic and negative delta H.
- Wed Nov 30, 2016 9:31 am
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: final yield question
- Replies: 2
- Views: 608
Re: final yield question
Remember Le Chatelier's Principle which states that chemical reactions adjust so as to minimize the effect of any changes. If you remove ammonia, the chemical reaction will adjust to minimize the effect of that change. Thus, to return back to equilibrium, more ammonia will be produced until the orig...
- Tue Nov 29, 2016 9:04 pm
- Forum: Acidity & Basicity Constants and The Conjugate Seesaw
- Topic: Ka/Kb question
- Replies: 4
- Views: 1098
Re: Ka/Kb question
Can someone please explain why strong acids and strong bases do not have Ka and Kb values? Is it because they dissociate 100% into products?
- Tue Nov 29, 2016 8:57 pm
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: Identifying a strong acid
- Replies: 6
- Views: 2250
Re: Identifying a strong acid
I was struggling trying to memorize the 7 strong acids we need to memorize! I looked up easy ways to remember them and I found this, it is so helpful! Someone posted: "My chemistry teacher taught us a way to memorize the strong acids. I hope this is helpful: "[I] [Br]ought [Chlorine] into ...
- Tue Nov 15, 2016 6:20 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Coordination Number for (en) [ENDORSED]
- Replies: 6
- Views: 2850
Re: Coordination Number for (en) [ENDORSED]
So since en is bidentate? Is dien tridentate because it has 3 nitrogens?
- Mon Nov 07, 2016 7:30 am
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: Number of Molecular Orbitals
- Replies: 2
- Views: 716
Re: Number of Molecular Orbitals
Then, after determining whether you're looking at a pi bond or a sigma bond, you assign the hybridization orbital in order to go along with it. For example, if you were looking at the CH(subscript 2)(double bond)CHCHO, The first C would have three regions of electron densities, thus the hybridizatio...
- Mon Nov 07, 2016 7:18 am
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: Number of Molecular Orbitals
- Replies: 2
- Views: 716
Re: Number of Molecular Orbitals
The key is to not over think it! In a single bond, there is one sigma bond. In a double bond, there is one sigma and one pi bond. In a triple bond, there is one sigma and two pi bonds.
- Sun Nov 06, 2016 10:49 am
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: 4.61 Homework Question
- Replies: 3
- Views: 925
Re: 4.61 Homework Question
There is a typo in the textbook answer! 22 should be 2 and 11 should be just 1 so don't worry you are doing it correctly. CO: (sigma2s)^2(sigma*2s)^2(pi2p)^4(sigma2p)^2 CO+: (sigma2s)^2(sigma*2s)^2(pi2p)^4(sigma2p)^1 Remember it is in this order because for hetronuclear with z mixed, you use the MO ...
- Sat Nov 05, 2016 2:44 pm
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: Energy Level differences depending on Z
- Replies: 1
- Views: 571
Re: Energy Level differences depending on Z
the course reader explains this on page 110. Because the nuclear charge is less for atoms z<8, the energy difference between filled s-orbitals and p-orbitals is less. The electron density from filled sigma(2s) and sigma*(2s) orbitals is concentrated along the bond axis. Since the sigma(2Pz) orbitals...
- Fri Oct 28, 2016 11:41 pm
- Forum: Polarisability of Anions, The Polarizing Power of Cations
- Topic: Dipole moments
- Replies: 1
- Views: 683
Re: Dipole moments
This is a little difficult to explain through typing. The definition of a dipole moment can be simplified by the equation: the Greek letter mu= Q(magnitude of the charge) x d (distance between those charges). We most likely won't have to show any math for this. However, we must know how to ANALYZE a...
- Sat Oct 22, 2016 9:38 pm
- Forum: Resonance Structures
- Topic: Resonance Structures-More Stable
- Replies: 2
- Views: 741
Resonance Structures-More Stable
Hi everyone! I understand resonance structures (resonance is a blending of structures with same arrangements of atoms but different arrangements of electrons). However, I am a little confused as to how being able to draw multiple resonance structures for a certain molecule proves that that molecule ...
- Fri Oct 14, 2016 6:26 pm
- Forum: Photoelectric Effect
- Topic: Threshold Energy
- Replies: 1
- Views: 606
Re: Threshold Energy
The signs are always conventional. It's right with or without the sign but it depends on how the question was being asked.
- Tue Oct 04, 2016 7:35 pm
- Forum: Properties of Light
- Topic: Speed of light [ENDORSED]
- Replies: 3
- Views: 974
Speed of light [ENDORSED]
I know this may be a stupid question, but I am really behind in chemistry...Is the speed of light always 3.00 x 10^8 meters per second? Or just in a vacuum?
- Tue Oct 04, 2016 7:28 pm
- Forum: General Science Questions
- Topic: Rusty on High School Chem [ENDORSED]
- Replies: 347
- Views: 416351
Re: Rusty on High School Chem [ENDORSED]
I also use a lot of Khan Academy videos! I know little about chem (last time i took it was my sophomore year of high school and it wasn't an AP course), so this class is extremely difficult for me. I am REALLY struggling, but I've been watching Khan Academy videos all day today trying to brush up on...
- Sat Oct 01, 2016 11:05 am
- Forum: Student Social/Study Group
- Topic: Sunset Village Study Group
- Replies: 17
- Views: 3499
Re: Sunset Village Study Group
I live in Hedrick Summit, but i am in desperate need of help! I am down to join