Search found 21 matches
- Sat Mar 18, 2017 1:04 am
- Forum: General Rate Laws
- Topic: Coefficients in rate laws
- Replies: 1
- Views: 505
Coefficients in rate laws
Is there ever a time when one should take the coefficient that is in front of a reactant in an equation, and use it as an exponent for that reactant in the equation's rate law? Is there a rule regarding taking the coefficients and using them as the exponent as well?
- Mon Mar 13, 2017 12:34 am
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3862763
Re: Post All Chemistry Jokes Here
Want to hear a joke about Sodium Hypobromite?
NaBrO.
NaBrO.
- Mon Mar 06, 2017 1:06 am
- Forum: *Cycloalkanes
- Topic: Selecting the name with the lowest number
- Replies: 1
- Views: 387
Selecting the name with the lowest number
During lecture on Friday, under the section of naming cycloalkanes, I was confused as to how the numbering of the carbons occurred in the case where there are 2 substituents on a ring. How does one decide when to start numbering off the carbons? I understand that it starts at a substituent molecule,...
- Mon Mar 06, 2017 1:02 am
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3862763
Re: Post All Chemistry Jokes Here
The optimist sees the glass half full. The pessimist sees the glass half empty. The chemist sees the glass completely full, half with liquid and half with air.
- Sun Feb 26, 2017 9:25 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3862763
Re: Post All Chemistry Jokes Here
Chemistry is like cooking- just don't lick the spoon!
- Tue Feb 14, 2017 2:38 pm
- Forum: Third Law of Thermodynamics (For a Unique Ground State (W=1): S -> 0 as T -> 0) and Calculations Using Boltzmann Equation for Entropy
- Topic: Midterm 2012 Question 3A
- Replies: 1
- Views: 482
Midterm 2012 Question 3A
In this question, the solutions say that the number of orientations for BH2F is 3, but I am unsure as to how this value was gotten. How does one figure out the orientations of the molecule to use that value in calculating the residual entropy?
- Sun Feb 12, 2017 5:54 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Cell Diagram
- Replies: 1
- Views: 387
Cell Diagram
How does one know when to add H+ into a cell diagram? What should we look for when writing a cell diagram to tell us what to put in it other than the species involved in the reaction?
- Fri Feb 10, 2017 9:24 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Why O2 is not counted in Enthalpy and Gibb's Free Energy Calculations [ENDORSED]
- Replies: 1
- Views: 1054
Why O2 is not counted in Enthalpy and Gibb's Free Energy Calculations [ENDORSED]
In problems in the homework, when there is calculations for the enthalpy of a reaction and the calculation for Gibb's Free energy, the molecule O2 was not included in the calculation, however, in the entropy calculations, I noticed that O2 is included. Is this because it is a diatomic molecule? Why ...
- Sun Feb 05, 2017 4:35 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3862763
Re: Post All Chemistry Jokes Here
Why did the white bear dissolve in water?
Because it was polar.
Because it was polar.
- Sun Jan 29, 2017 11:18 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Calculating Degeneracy
- Replies: 2
- Views: 702
Calculating Degeneracy
I understand the equation for calculating degeneracy is W=2^N, however, in which cases will this equation be used? What exactly is W signifying and telling us?
- Sun Jan 22, 2017 2:20 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Example 8.13 in Textbook
- Replies: 2
- Views: 666
Example 8.13 in Textbook
In this example, the reaction is Br2(l) + CH3CH=Ch2(g) --> CH3CHBrCH2Br(l). I am confused as to how in the textbook, they say that two reactant bonds are broken, specifically the Br2 and double bond in CH3CH=Ch2, and three bonds are formed in the product, C-C and two C-Br. However, when I drew out t...
- Sat Dec 03, 2016 12:12 pm
- Forum: *Titrations & Titration Calculations
- Topic: Stoichiometric Point, Halfway Stoichiometric Point from graph
- Replies: 1
- Views: 2982
Stoichiometric Point, Halfway Stoichiometric Point from graph
How do you distinguish the stoichiometric point, the halfway stoichiometric point, and the pKa value from looking at a titration graph? Also, how do you know from a titration graph what two things are being reacted (strong base/strong acid, strong base/weak acid, strong acid/weak base, weak acid/wea...
- Sun Nov 27, 2016 1:51 pm
- Forum: Acidity & Basicity Constants and The Conjugate Seesaw
- Topic: Ka1,2,3... Significance
- Replies: 1
- Views: 589
Ka1,2,3... Significance
In my notes, I have written that Ka1>Ka2>Ka3... as it is harder to lose H+ from a negatively charged ion, as they are more stable. However, I do not understand what Ka2 and Ka3 and so on are, Ka1 would be found by taking the initial products and reactants in an equation, but what changes in the equa...
- Sun Nov 20, 2016 12:42 am
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Pressure/Expansion effect on products and reactants
- Replies: 2
- Views: 658
Pressure/Expansion effect on products and reactants
What is the effect of an increase in pressure, and an increase in expansion on an equilibrium equation with more moles of reactant on the left side of the equation as compared to moles of product? Why is this the case?
- Fri Nov 11, 2016 2:14 pm
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: Order of Filling and Removing Electrons in M.O. Diagrams
- Replies: 1
- Views: 668
Order of Filling and Removing Electrons in M.O. Diagrams
What is the correct order to fill an M.O. diagram for atoms with total electrons less that 8 and more than 8? Also, if there is a homonuclear compound, then the M.O. is symmetric on both sides, and you would follow the order to fill as given, but what changes when it is a heteronuclear compound, and...
- Sun Oct 30, 2016 11:48 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Linear vs. Bent Molecular Shape
- Replies: 4
- Views: 23061
Linear vs. Bent Molecular Shape
In molecules where the Lewis structure is three elements put together, how do we know whether the molecular shape for those molecules is linear or bent? For instance, ClO2+ has a structure with Cl being the center atom with a lone pair and two Oxygens double bonding to it, how can one know why it ha...
- Sat Oct 29, 2016 12:07 am
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: Bond Order and Antibonding Orbitals
- Replies: 1
- Views: 655
Bond Order and Antibonding Orbitals
What exactly is an antibonding orbital, and how exactly does a molecular orbital energy level diagram show how an antibonding orbital has less energy than a bonding orbital? Also, what is the purpose of figuring out the bond order, is it just to know how many bonds are made in a molecule?
- Fri Oct 21, 2016 10:54 pm
- Forum: Coordinate Covalent Bonds
- Topic: Electron Distortion and Chemical Bonds
- Replies: 1
- Views: 6100
Electron Distortion and Chemical Bonds
What exactly is electron distortion, and how does this lead to ionic bonds having covalent bond characteristics? What does it mean when an ion has a high distortion, and thus has a high polarizing power, and how are these concepts related to the fact that ionic bonds have slightly covalent character...
- Fri Oct 14, 2016 7:11 pm
- Forum: Ionic & Covalent Bonds
- Topic: The Octet Rule (and exceptions)
- Replies: 1
- Views: 807
The Octet Rule (and exceptions)
Looking over my notes, I noticed and remembered from lecture that there are exceptions to the octet rule. I understood the exception for Hydrogen, Helium, Lithium, and Beryllium, but am confused for the exception regarding those in the third period (and especially how they can have more than 8 valen...
- Fri Oct 07, 2016 10:30 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Assigning Spin to States
- Replies: 1
- Views: 467
Assigning Spin to States
In the lecture, the concept of assigning spin (positive or negative) to states of atoms was discussed. However, it is still unclear to me how to actually write in the spin orientation for different states. I do not know, for instance, how to take a Neon atom, and analyze its states and assign the el...
- Fri Sep 30, 2016 5:46 pm
- Forum: Properties of Electrons
- Topic: Energy Absorption and Emission for Electrons
- Replies: 3
- Views: 683
Energy Absorption and Emission for Electrons
In my notes from today's lecture, I wrote a statement that says: the energy of light that is absorbed or emitted matches the energy difference of an electron moving from one principal quantum level to the other. Can someone clarify and further explain this concept? Does this mean that the energy tha...