Search found 21 matches
- Sat Mar 18, 2017 5:17 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Pre-Equilibrium Approach ?
- Replies: 1
- Views: 533
Re: Pre-Equilibrium Approach ?
It can be used to determine which step in a reaction process is the rate-limiting step. By taking each step of a reaction, we write the rate law for it like k[R][R2] and substitute the intermediates, and then see if it matches the overall reaction rate. An example of this can be seen in the winter 2...
- Wed Mar 15, 2017 10:16 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Intermediates and Transition States
- Replies: 1
- Views: 495
Intermediates and Transition States
I often get transition states and intermediates confused in reactions 2 step reactions, what is a way to clearly distinguish them from each other?
- Sun Mar 12, 2017 2:44 pm
- Forum: *Aldehydes
- Topic: trans and cis attachments to cyclic carbon structures
- Replies: 1
- Views: 1299
trans and cis attachments to cyclic carbon structures
I am confused on how you are able to tell whether a substituent is attached trans or cis to a cyclic carbon structure. In the Introduction to Organic Chemistry textbook page 60, there is an example molecule of cinnamaldehyde, and its IUPAC name includes E because the aldehyde is attached trans to ca...
- Tue Mar 07, 2017 11:35 pm
- Forum: *Cycloalkenes
- Topic: Z vs. E
- Replies: 2
- Views: 722
Re: Z vs. E
How exactly would the substituents affect whether the molecule was cis or trans? Would it change by how you begin to count the carbon atoms in the ring?
- Mon Mar 06, 2017 11:37 pm
- Forum: *Alkenes
- Topic: question 1.11
- Replies: 1
- Views: 539
question 1.11
The name of the molecule (CH3)2CHCCCH2CH3 was given as 2-methyl-3-hexyne. However, I had thought that the triple bonded carbon would be given the priority of having the lowest number, so I had thought the name would be something like 5-diethyl-3-hexyne. Does this mean that regardless of whether ther...
- Wed Feb 22, 2017 10:48 am
- Forum: Method of Initial Rates (To Determine n and k)
- Topic: assuming order from units of k
- Replies: 1
- Views: 470
assuming order from units of k
In questions where the order is not given but k is, is it possible to assume the order from the units of k? For example, observing that k is in units of seconds^-1 or minutes^-1 then assuming it is a first order reaction, or if k is in liters per mole per second, then it assuming it is a second orde...
- Mon Feb 06, 2017 10:30 am
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Inert Conductor in cell diagrams
- Replies: 1
- Views: 553
Inert Conductor in cell diagrams
How can you tell when drawing a cell diagram whether an inert conductor such as Pt is needed? What features of the cells should I look for?
- Sun Feb 05, 2017 3:30 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: magnesium metal production in course reader [ENDORSED]
- Replies: 2
- Views: 616
magnesium metal production in course reader [ENDORSED]
While I understand the role of the external current supply in forcing an electron current to allow production of the solid magnesium, I'm confused on why the redox reactions for the anode and cathode have a large negative E value in the first place?
- Sat Feb 04, 2017 9:52 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2760024
Re: Post All Chemistry Jokes Here
Organic chemistry is difficult. Those who study it have alkynes of trouble.
- Sat Jan 28, 2017 4:10 pm
- Forum: Calculating Work of Expansion
- Topic: Homework 8.1
- Replies: 1
- Views: 479
Homework 8.1
I'm wondering why the change in volume is converted from cubic centimeters to liters. Is it to accommodate the relationship between atm and L to Joules? A little confused on the conversions and relations between these various measurements.
- Wed Jan 18, 2017 2:24 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Question 8.31
- Replies: 4
- Views: 702
Re: Question 8.31
I've looked at the corresponding section in the textbook explaining why CP,m=(5/2)R, but I'm still lost on how to obtain the value 20.8 J per mols per degrees C that was in the solutions manual for question 31 from that equation.
- Tue Nov 29, 2016 11:17 am
- Forum: Amphoteric Compounds
- Topic: Is In2O3 basic or amphoteric?
- Replies: 2
- Views: 3688
Re: Is In2O3 basic or amphoteric?
Could you explain why if there are more oxygens attached to the central atom, then it's more acidic? Could I use this fact to classify other compounds as either more basic or acidic?
- Sat Nov 19, 2016 12:45 am
- Forum: Lewis Acids & Bases
- Topic: Textbook Problem
- Replies: 1
- Views: 554
Textbook Problem
I'm a bit confused on how to approach problem number 107 in chapter 12; How do you tell which image shows the stronger or weaker acid?
- Sat Nov 12, 2016 11:31 pm
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: HOMO to LUMO
- Replies: 1
- Views: 557
HOMO to LUMO
Although I understand the basis of HOMO to LUMO interaction, I'm still a little confused how it's applied to UV and visible light absorption spectrum. Could someone explain this relation?
- Wed Nov 02, 2016 4:10 pm
- Forum: Ionic & Covalent Bonds
- Topic: Ionic character
- Replies: 2
- Views: 765
Re: Ionic character
In this case I don't think you look at the electronegativity differences, but at the bonds themselves...HCl is covalently bonded while LiH is has an ionic bond (H takes an electron from the cation Lithium so it can reach the noble gas configuration for He), so I think naturally LiH would have a more...
- Thu Oct 27, 2016 12:42 pm
- Forum: Lewis Structures
- Topic: Expanded Octet
- Replies: 3
- Views: 813
Re: Expanded Octet
Elements that are in period three or higher, along with those with d orbitals can have more than 8 electrons. So P, S, Cl, and after can usually be exceptions to the rule, even noble gases as well like Xe can have more than 8 valence electrons and form compounds.
- Sat Oct 22, 2016 10:57 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: f orbitals
- Replies: 1
- Views: 525
f orbitals
I'm a bit confused on how the f orbtal shell orbital is incorporated into the electron configuration of hafnium. Why is it that it is already full with 14 electrons?
- Sun Oct 16, 2016 3:15 am
- Forum: *Shrodinger Equation
- Topic: Kinetic energy in the Schrodinger equation
- Replies: 1
- Views: 1190
Re: Kinetic energy in the Schrodinger equation
Hi Erik, I've had trouble understanding this as well, but the link below has a helpful section on why wave functions in the Quantum World allow for negative kinetic energy. http://www.bu.edu/quantum/notes/QuantumMechanics/TheSchrodingerEquation.pdf In a really rough summary of the section: while in ...
- Fri Oct 07, 2016 11:55 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: Question G21 [ENDORSED]
- Replies: 1
- Views: 724
Question G21 [ENDORSED]
The question is as follows: A solution is prepared by dissolving 0.500g of KCl, 0.500g of K2S, and 0.500g of K3PO4 in 500 mL of water. For part a, it asks for the concentration in the final solution of potassium ions. Where I'm confused is how to calculate a specific ion within a solution's molarity...
- Mon Oct 03, 2016 12:10 am
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Building-Up Principle [ENDORSED]
- Replies: 3
- Views: 4328
Re: Building-Up Principle [ENDORSED]
Thank you so much! The video and your examples were very helpful :)
- Sat Oct 01, 2016 12:33 am
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Building-Up Principle [ENDORSED]
- Replies: 3
- Views: 4328
Building-Up Principle [ENDORSED]
I'm a bit confused on how the building-up principle leads to an excited state of an electron, as well as how its excited state configuration compares with its ground state configuration. For example, just from looking at an atom's electron configuration, how can you determine that it is in an excite...