Search found 11 matches
- Fri Mar 17, 2017 7:19 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Saying Thank You to Dr. Lavelle
- Replies: 490
- Views: 504283
Re: Saying Thank You to Dr. Lavelle
Dr. Lavelle! Thank you so much for being such a passionate teacher and an inspiration to us all. The joy that you expressed teaching is something that we can only hope for as we continue our journey towards our careers. You care for your students so deeply, and because of that, you make us all feel ...
- Sun Mar 05, 2017 9:58 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2763261
Re: Post All Chemistry Jokes Here
What is a snake's favorite law?
Hesssss's Law!
Hesssss's Law!
- Mon Feb 27, 2017 6:43 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2763261
Re: Post All Chemistry Jokes Here
Brrrrrrromine!
What? Bromine?
Yeah, it's cold! Brrrrrrr.
What? Bromine?
Yeah, it's cold! Brrrrrrr.
- Tue Feb 21, 2017 10:46 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2763261
Re: Post All Chemistry Jokes Here
"Wow, you must travel a lot, how many states have you been in?"
"Find my entropy and you'll know!"
"Find my entropy and you'll know!"
- Thu Feb 09, 2017 2:16 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: q=mC(T2-T1) vs q=C(T2-T1)
- Replies: 1
- Views: 5336
q=mC(T2-T1) vs q=C(T2-T1)
As an example, problem 8.23 says: A calorimeter was calibrated with an electric heater, which supplied 22.5 kJ of energy as heat to the calorimeter and increased the temperature of the calorimeter and its water bath from 22.45 degrees celsius to 23.97 degrees celsius. What is the heat capacity of th...
- Wed Feb 08, 2017 10:42 am
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2763261
Re: Post All Chemistry Jokes Here
A boy asked his mom to make him a Pb and J sandwich. However, after eating the sandwich, he complained that he felt quite heavy.
- Tue Jan 17, 2017 11:13 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Error on 8.63c
- Replies: 2
- Views: 465
Re: Error on 8.63c
Yup! You're correct. I made a post asking the same thing, and here's what Chem_Mod replied: "This error, as well as others, can be found in the Solutions Manual Errors document located on the course website." Hope that helps!
- Tue Jan 17, 2017 6:31 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: There is an error in the Solutions Manual on question 8.63 (c.)
- Replies: 1
- Views: 366
There is an error in the Solutions Manual on question 8.63 (c.)
Writing simply to help, in the solutions manual it states that for 8.63 (c.), the value for K2S(aq) is -417.5 kJ per mole, however, based on the textbook, it should actually be -471.5 kJ. So your answer should actually be -38.72 kJ. :)
- Tue Jan 17, 2017 5:53 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Hess' Law [ENDORSED]
- Replies: 5
- Views: 2769
Re: Hess' Law [ENDORSED]
You are right that when we make changes to reactions we need to change the enthalpy, but that is only true if the change affects the whole reaction. In relation to your example, let me demonstrate with problem 8.57. Here, one of the equations we need to balance is H2(g)+O2(g)---->H2O(l). We are told...
- Tue Jan 17, 2017 5:34 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: kJ vs. kJ per mole?
- Replies: 3
- Views: 942
kJ vs. kJ per mole?
I have currently worked through problems 8.57, 8.59, 8.61, and 8.63 (part a), and they all seem like they are asking for the same thing- the standard reaction enthalpy. However, I don't understand then why the answer in 8.57 and 8.59 is in kJ per mole and the answer for 8.61 and 8.63 (just looking a...
- Mon Jan 16, 2017 11:15 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Eq. 20?
- Replies: 1
- Views: 291
Eq. 20?
While reading through Standard Enthalpies of Formation (8.17), I ran across an example that asked us to reference back to something called Eq. 20. ("Use Eq. 20 and the procedure set out in example 8.10..." - top of pg 297). Does anyone know what it is, or where I can find it?