Search found 20 matches
- Mon Mar 06, 2017 9:03 pm
- Forum: *Organic Reaction Mechanisms in General
- Topic: Organic Reaction Mechanisms
- Replies: 1
- Views: 399
Re: Organic Reaction Mechanisms
If you look at a PEDD diagram(graph), the energy in the transition state is always higher than the reactants. This means that from the reactants to the transition state, \Delta G standard will always be positive and unfavorable. If this were not the case, the transition state would not be the transi...
- Mon Mar 06, 2017 8:56 pm
- Forum: *Cycloalkenes
- Topic: Naming Techniques
- Replies: 1
- Views: 297
Re: Naming Techniques
I would draw it out completely, this helps me. When drawing it out, try to make straight lines of all the possible parent chains and find th longest one. Numbering the carbons helps too
- Fri Mar 03, 2017 2:36 pm
- Forum: *Cycloalkanes
- Topic: Common Names
- Replies: 3
- Views: 532
Re: Common Names
When carbon chains are in the specific compositions mentioned in the course reader, the substituent is given an iso- prefix. In any other arrangement, iso- is not included in naming. For example, -< this skeletal structure substituent would be named isopropyl. Basically iso- is used when the middle ...
- Wed Feb 22, 2017 10:22 pm
- Forum: General Rate Laws
- Topic: Half Life Equation graph
- Replies: 1
- Views: 280
Re: Half Life Equation graph
Only the integrated rate law will be linear. Half life is never linear. You only plot the rate law to determine which order it is.
- Wed Feb 15, 2017 3:03 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: How to write electrode reactions from a cell diagram & write a cell diagram from overall reaction?
- Replies: 2
- Views: 543
Re: How to write electrode reactions from a cell diagram & write a cell diagram from overall reaction?
Try writing out the half-reactions for each problem. That should make things more clear
- Fri Feb 10, 2017 8:23 pm
- Forum: Balancing Redox Reactions
- Topic: Oxidation Numbers
- Replies: 2
- Views: 384
Re: Oxidation Numbers
All elements have a zero oxidation charge All molecules have the charge specified (some you may have to memorize) Group 1 elements are always +1 Group 2 elements are usually +2 Chalcogens are usually -2 Halogens are usually -1 The charges of the ions have to equal the charge of the total molecule
- Fri Feb 03, 2017 3:28 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: 9.43
- Replies: 2
- Views: 439
Re: 9.43
At constant pressure, use
Cvln (T2/T1) and S tot= kBln W1W2
T=Tfinal-Tinitial
- Sun Jan 29, 2017 7:22 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Question on Units of Temperature
- Replies: 4
- Views: 519
Re: Question on Units of Temperature
When there is a temperature change of 1 degree Celsius, there's also a temperature change of 1 degree Kelvin (and vice versa). This means they're interchangeable (one-to-one conversion).
- Thu Jan 19, 2017 5:11 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Practice Quizzes
- Replies: 3
- Views: 491
Re: Practice Quizzes
Not anymore
- Fri Jan 13, 2017 7:07 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Problem 8.65
- Replies: 3
- Views: 388
Re: Problem 8.65
the desired reaction is: N2(g)+5/2 O2(g)--> N2O5(g)
Divide the second reaction by 2 and add the first and second together to get: 2 NO(g)+3/2 O2(g)--> N2O5(g) with an enthalpy of-169.2 kJ.
Then calculate the standard enthalpy of formation
Divide the second reaction by 2 and add the first and second together to get: 2 NO(g)+3/2 O2(g)--> N2O5(g) with an enthalpy of-169.2 kJ.
Then calculate the standard enthalpy of formation
- Tue Nov 29, 2016 4:57 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Quantum Numbers 1 and 2
- Replies: 1
- Views: 352
Re: Quantum Numbers 1 and 2
As energy levels increase, the gap between them decreases
- Mon Nov 28, 2016 2:31 pm
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: Calculating pH and Ionization percentage
- Replies: 1
- Views: 322
Re: Calculating pH and Ionization percentage
To find the percentage of ionization in acetic acid, you have to find the concentration of H3O+ because you have to see how much acetic acid dissociates (ionizes). By finding this concentration, you know what percentage of acetic acid ionized into H3O+. The pH is -log [H3O+]
- Fri Nov 18, 2016 9:15 pm
- Forum: Bronsted Acids & Bases
- Topic: Bronsted acid and bases
- Replies: 1
- Views: 373
Re: Bronsted acid and bases
In this case, H2O is the Broasted-Lowry base because it accepts an H+ (which is basically a proton)
- Wed Nov 09, 2016 7:51 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Equilibrium Constant
- Replies: 3
- Views: 600
Re: Equilibrium Constant
Use concentrations, but make sure all are converted into concentrations.
- Tue Nov 01, 2016 7:42 pm
- Forum: Sigma & Pi Bonds
- Topic: Sigma and Pi bond hybridization
- Replies: 2
- Views: 419
Re: Sigma and Pi bond hybridization
Yes. The s orbital cannot have pi bonds because there are only two sub-orbitals. The p orbital can because after two of the sub-orbitals bond, there are four available to make up to two pi bonds
- Wed Oct 26, 2016 10:31 pm
- Forum: Lewis Structures
- Topic: 3.103
- Replies: 1
- Views: 279
Re: 3.103
A proton is identical to H+, or a Hydrogen atom without an electron. In the molecule above, the H+ will be attracted to the slightly negative Oxygen. When drawing Lewis structures, H+ is a good representation of a proton and is commonly interchangeable.
- Tue Oct 18, 2016 3:39 pm
- Forum: Lewis Structures
- Topic: Charges When Drawing Lewis Structure [ENDORSED]
- Replies: 2
- Views: 499
Re: Charges When Drawing Lewis Structure [ENDORSED]
As Lavelle was saying, you use the octet rules as guideline for transferring electrons. Likewise, you can use the same guideline to know the charges of the elements when doing Lewis structures. For example, Oxygen likes gain two electrons to make an octet, so the ion will generally have a charge of ...
- Thu Oct 13, 2016 3:43 pm
- Forum: Balancing Chemical Reactions
- Topic: Balancing Chemical equations too slow... any advice? [ENDORSED]
- Replies: 18
- Views: 1984
Re: Balancing Chemical equations too slow... any advice? [ENDORSED]
Also, balance Oxygen last if it is present. It tends to be a little more difficult so balancing it last saves some time.
- Wed Oct 05, 2016 9:13 pm
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: Post Module Question #8/9 [ENDORSED]
- Replies: 3
- Views: 722
Re: Post Module Question #8/9 [ENDORSED]
Try using the equation KE=1/2 mv^2
You should get the kinetic energy for one hydrogen atom. From there you can use dimensional analysis to calculate the kinetic energy per mole of electrons/hydrogen atoms.
You should get the kinetic energy for one hydrogen atom. From there you can use dimensional analysis to calculate the kinetic energy per mole of electrons/hydrogen atoms.
- Thu Sep 29, 2016 2:50 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: 1.11 Different Series
- Replies: 3
- Views: 646
1.11 Different Series
Question 1.11 states, "In the spectrum of atomic hydrogen, several lines are generally classified together as belonging to a series (for example, Balmer series, Lyman series, Paschen series), as shown in Figs. 1.10 and 2.1. What is common to the lines within a series that makes groupie them tog...