Search found 22 matches
- Sun Mar 05, 2017 5:16 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 4085083
Re: Post All Chemistry Jokes Here
A photon checks into a hotel and is asked if he needs any help with his luggage. He says, "No, I'm traveling light."
- Thu Feb 23, 2017 11:03 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 4085083
- Mon Feb 13, 2017 9:40 pm
- Forum: Student Social/Study Group
- Topic: Quiz 1 #1 and #7
- Replies: 1
- Views: 530
Quiz 1 #1 and #7
If anyone in section 3J got #1 and/or #7 right on the quiz and would be willing to explain I would really appreciate it. I would write out the questions but there are a lot of subheadings that make it kind of hard. :/ Thanks in advance!
- Sat Feb 11, 2017 12:55 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Work [ENDORSED]
- Replies: 1
- Views: 502
Re: Work [ENDORSED]
When work is done on the system, it's positive. When work is done by the system, it's negative.
- Fri Feb 03, 2017 10:26 am
- Forum: Administrative Questions and Class Announcements
- Topic: Quiz 1 Preparation Answers
- Replies: 130
- Views: 25944
Re: Quiz 1 Preparation Answers
#8 on Quiz 1 Preparation says, "For reaction: 2C+2H2=C2H4, DeltaH= +52.3 kJ/mol and DeltaS= -53.07 J/K*mol at 298 K. At what temperature will this reaction be spontaneous?" Initially, I thought the formula needed to solve for the temperature was DeltaG= DeltaH - T*DeltaS but then I saw th...
- Tue Jan 31, 2017 12:53 am
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Conceptualizing the Boltzmann Equation
- Replies: 1
- Views: 548
Re: Conceptualizing the Boltzmann Equation
it's basically saying any error in W, even a relatively large one, wouldn't cause a large error in S
so no, a small error in W wouldn't cause a large error in S
so no, a small error in W wouldn't cause a large error in S
- Sun Jan 29, 2017 6:41 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 4085083
Re: Post All Chemistry Jokes Here
Exothermic reactions?
I studied them before they were cool.
I studied them before they were cool.
- Thu Jan 26, 2017 10:10 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Finals from 14A
- Replies: 1
- Views: 547
Re: Finals from 14A
The email from last quarter says 4006 Young Hall :)
- Fri Jan 20, 2017 4:21 pm
- Forum: Calculating Work of Expansion
- Topic: HW Problem 8.93
- Replies: 1
- Views: 564
Re: HW Problem 8.93
The products of a combustion reaction are always carbon dioxide and water.
- Fri Jan 20, 2017 4:16 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Bond Enthalpy [ENDORSED]
- Replies: 1
- Views: 563
Re: Bond Enthalpy [ENDORSED]
Yes, I believe so.
- Mon Jan 16, 2017 1:06 am
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Heat and Temperature
- Replies: 1
- Views: 588
Re: Heat and Temperature
Heat (Q) is energy. It is the total amount of energy (both kinetic and potential) possessed by the molecules in a piece of matter. Heat is measured in Joules. Temperature (T) is not energy. It relates to the average (kinetic) energy of microscopic motions of a single particle in the system per degre...
- Sat Jan 14, 2017 4:58 pm
- Forum: Administrative Questions and Class Announcements
- Topic: How to change our username
- Replies: 1
- Views: 476
Re: How to change our username
All you have to do it click your current username at the top right then click user control panel. Once you do that just change your username and put in your current password and you're all set!
- Sun Nov 20, 2016 2:42 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 4085083
Re: Post All Chemistry Jokes Here
A photon checks into a hotel and is asked if he needs any help with his luggage. He says, "No, I'm traveling light."
- Thu Nov 17, 2016 1:54 am
- Forum: Hybridization
- Topic: Polar/nonpolar [ENDORSED]
- Replies: 14
- Views: 2721
Re: Polar/nonpolar [ENDORSED]
Bonds that are partially ionic are polar. Nonpolar bonds have an equal sharing of electrons.
- Sat Nov 12, 2016 5:54 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: K value
- Replies: 1
- Views: 568
Re: K value
Because their concentrations pretty much stay constant.
- Fri Nov 04, 2016 8:35 pm
- Forum: Lewis Acids & Bases
- Topic: Fall 2014 Midterm Question 2B
- Replies: 2
- Views: 761
Re: Fall 2014 Midterm Question 2B
Yes. A lewis acid is an electron acceptor and a lewis base is an electron donor.
- Tue Nov 01, 2016 6:20 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: chart of shapes
- Replies: 1
- Views: 692
- Mon Oct 31, 2016 1:15 am
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 4085083
Re: Post All Chemistry Jokes Here
I asked the guy sitting next to me if he had any Sodium Hypobromite…
He said NaBrO
He said NaBrO
- Thu Oct 20, 2016 8:44 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Formal Charge of 0 [ENDORSED]
- Replies: 3
- Views: 2821
Re: Formal Charge of 0 [ENDORSED]
A formal charge of zero means the atom has the best balance of bonds to lone pairs according to its valence (meaning it's stable).
- Fri Oct 14, 2016 7:38 pm
- Forum: Ionic & Covalent Bonds
- Topic: The Octet Rule (and exceptions)
- Replies: 1
- Views: 809
Re: The Octet Rule (and exceptions)
"some of the third-period elements (Si, P, S, and Cl) have been observed to bond to more than four other atoms, and thus need to involve more than the four pairs of electrons available in an s2p6 octet. This is possible because for n=3, the d sublevel exists, and it has five d orbitals." S...
- Sat Oct 08, 2016 9:12 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 4085083
Re: Post All Chemistry Jokes Here
Q: What do you do with a dead chemist?
A: Barium
A: Barium
- Fri Sep 30, 2016 5:25 pm
- Forum: Properties of Light
- Topic: calculating wavelength [ENDORSED]
- Replies: 3
- Views: 988
Re: calculating wavelength [ENDORSED]
They are converting to Joules.
1 eV = 1.602177x10-19 Joule
1 eV = 1.602177x10-19 Joule