Search found 21 matches
- Sat Mar 18, 2017 1:30 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: PdeltaV=deltanRT
- Replies: 4
- Views: 6013
PdeltaV=deltanRT
When do you use PdeltaV=deltanRT?
- Fri Mar 17, 2017 12:10 am
- Forum: *Cyclohexanes (Chair, Boat, Geometric Isomers)
- Topic: Stability of chair and boat isomers
- Replies: 1
- Views: 473
Stability of chair and boat isomers
How do you know that the CH2s in the boat configuration are closer together than those in the chair configuration? Then, due to fewer electron-electron repulsions, the chair configuration would have a lower potential energy and thus a higher stability right?
- Thu Mar 16, 2017 8:36 pm
- Forum: *Electrophilic Addition
- Topic: Electrophilic Addition
- Replies: 2
- Views: 1481
Electrophilic Addition
For an electrophilic addition reaction mechanism of a compound with a double bond and HBr, does the carbon to which the H is added matter?
- Mon Mar 13, 2017 6:48 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Final Exam Winter 2014 Question 2A
- Replies: 1
- Views: 394
Final Exam Winter 2014 Question 2A
Question 2A:
For the reaction 2CO(g)+O2(g)-->2CO2(g)
Without doing calculations, predict the sign of Change in entropy of the system.
How do we know that the change in entropy of the system is less than 0?
For the reaction 2CO(g)+O2(g)-->2CO2(g)
Without doing calculations, predict the sign of Change in entropy of the system.
How do we know that the change in entropy of the system is less than 0?
- Wed Mar 08, 2017 8:08 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3055314
Re: Post All Chemistry Jokes Here
Alkene joke
- Wed Mar 08, 2017 8:06 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3055314
Re: Post All Chemistry Jokes Here
Alkane joke
- Wed Mar 08, 2017 8:04 pm
- Forum: *Organic Reaction Mechanisms in General
- Topic: Describing reactions
- Replies: 2
- Views: 621
Describing reactions
When do you use endergonic and exergonic as opposed to exothermic and endothermic?
- Tue Feb 14, 2017 1:46 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Winter 2013 Midterm 8B
- Replies: 1
- Views: 375
Winter 2013 Midterm 8B
For Q8B on the Winter 2013 Midterm, how is n 8? Where are the electrons being transferred in this equation?: Fe(s) (+) 2Ce4+ -->Fe2+ (+) 2Ce3+
- Sun Feb 12, 2017 1:17 am
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Gibbs Free Energy and Stability
- Replies: 1
- Views: 1979
Gibbs Free Energy and Stability
For question 9.63, the answer key says that "Compounds with a positive free energy of formation are unstable with respect to the elements." Are spontaneous reaction not unstable (Gibbs free energy for spontaneous reactions is negative, right)?
- Sat Feb 11, 2017 11:23 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3055314
Re: Post All Chemistry Jokes Here
Someone studying atoms is really just a bunch of atoms trying to understand themselves.
- Sat Feb 11, 2017 7:16 pm
- Forum: Phase Changes & Related Calculations
- Topic: Change in Entropy [ENDORSED]
- Replies: 1
- Views: 461
Change in Entropy [ENDORSED]
For calculations involving (Delta S) = nRln(V2/V1), when can you assume that there is only 1 mol of the substance?
- Mon Nov 28, 2016 10:40 pm
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: Heteronuclear Diatomic Molecules
- Replies: 2
- Views: 647
Heteronuclear Diatomic Molecules
In a molecular orbital diagram for a heteronuclear diatomic molecule that has 1 element from groups 13-15 and another element from groups 16-18, what template must be used? Should the pi 2p orbitals have a lower energy than the sigma 2p or is it vice versa? For example, [BO]-
- Sun Nov 27, 2016 2:03 pm
- Forum: Identifying Acidic & Basic Salts
- Topic: Shortcut for determining acidity/basicity of salts
- Replies: 1
- Views: 1555
Shortcut for determining acidity/basicity of salts
Does this shortcut to determine the acidity/basicity of salts always work?
- Sun Nov 27, 2016 1:39 pm
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: Molecular orbital theory of diatomic molecules
- Replies: 1
- Views: 569
Molecular orbital theory of diatomic molecules
How should you structure a molecular orbital diagram for CO? What is the order of the sigma 2p and pi 2p orbitals?
- Sat Nov 26, 2016 6:25 pm
- Forum: Calculating the pH of Salt Solutions
- Topic: classifying acidity/basicity of NaClO
- Replies: 1
- Views: 1066
classifying acidity/basicity of NaClO
Because Na only has a 1+ charge, it cannot be considered an acidic cation right? So, ClO is the only ion reacting with water? Is it the only component in determining the pH of this salt solution? ClO- + H2O-<-> HClO + OH- Because ClO- is the conjugate base of a weak acid, NaClO is a basic salt right...
- Tue Nov 22, 2016 12:16 am
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3055314
Re: Post All Chemistry Jokes Here
Equilibrium constant. Que?
- Sat Nov 12, 2016 5:11 pm
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: Molecular Orbital CN- [ENDORSED]
- Replies: 1
- Views: 653
Molecular Orbital CN- [ENDORSED]
For the molecular orbital of CN- does it matter where the extra electron goes? Or, should it go in one of the 2p orbitals of C or N?
- Tue Oct 25, 2016 6:52 pm
- Forum: Lewis Structures
- Topic: Formal Charge
- Replies: 3
- Views: 596
Formal Charge
Is formal charge in any way related to polarity?
- Sat Oct 08, 2016 3:40 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Rydberg Equation [ENDORSED]
- Replies: 4
- Views: 1057
Rydberg Equation [ENDORSED]
Is it usually more efficient to use the Rydberg equation in these types of problems where frequency and an initial/final energy level are provided? In other words, when would you use E=-hR/n^2 over the Rydberg Equation?
- Thu Sep 29, 2016 2:19 pm
- Forum: Photoelectric Effect
- Topic: Minimum frequency needed to eject electrons
- Replies: 2
- Views: 974
Re: Minimum frequency needed to eject electrons
As work function increases does the ionization energy increase? So do metals with larger atomic radii have lower work functions?
- Thu Sep 29, 2016 2:08 pm
- Forum: Photoelectric Effect
- Topic: Minimum frequency needed to eject electrons
- Replies: 2
- Views: 974
Minimum frequency needed to eject electrons
In photoelectric experiments, typically what part of the electromagnetic spectrum is the incoming light? I understand that UV light is typically used, but what is the minimum frequency needed to eject electrons, albeit poorly?