layuplilley New Recruit 44 Posts user info edit post |
can anyone give me some ideas about #1 or 2. I think he worked something similar to 1 in class, but i can't find any of my notes, so any help is much appreciated. 10/28/2005 4:54:47 PM |
wildfaery Veteran 165 Posts user info edit post |
I always find myself waiting until the day before to do chemistry homework. I always put it off because I get so frustrated. I have a mtg with Franzen, my test grade sucked 10/30/2005 2:39:25 PM |
wildfaery Veteran 165 Posts user info edit post |
you can look in your book on pg 190 for help with number one 10/30/2005 3:28:14 PM |
Erfdawg All American 875 Posts user info edit post |
I don't understand how pg 190 helps with Q1. I see how the example is similar to Q1, but we don't know the boiling temp or the pressure at that altitude. I found an equation through wikipedia on how to find the atmosperic pressure with a given altitude but it isn't a formula he has ever shown us or that is in the book. The equation is:
logP=5-(h/15500) where h is height.
I can solve the problem if I use this formula but I am not sure if I am supposed to use it.
any help is appreciated. 10/30/2005 7:58:46 PM |
wildfaery Veteran 165 Posts user info edit post |
I used the C-C eq and used the pressure of .38atm roughly, b/c the 20000ft is roughly 6000m. 10/30/2005 8:50:38 PM |
wildfaery Veteran 165 Posts user info edit post |
how did you begin to do #2? 10/30/2005 9:12:09 PM |
Erfdawg All American 875 Posts user info edit post |
I am currently translating #2 into english.
For #1 I calculated the pressure at the top of Kilimanjaro as:
logP=5-(h/15500) P=10^(5-(6000/15500)) P=41011 Pascals P=0.405 atm
What value did you use for the Hvap? 10/30/2005 9:22:55 PM |
wildfaery Veteran 165 Posts user info edit post |
40.7kj/mol 10/30/2005 9:28:06 PM |
Joie begonias is my boo 22491 Posts user info edit post |
number 2 is problem #1 in chapter 5 of the book.....i'm trying to work backwards
so far, nothing 10/30/2005 9:36:17 PM |
wildfaery Veteran 165 Posts user info edit post |
thanks for the tip, so you're just looking at the answer in the back of the book and trying to figure it out?
[Edited on October 30, 2005 at 9:45 PM. Reason : .] 10/30/2005 9:44:11 PM |
Joie begonias is my boo 22491 Posts user info edit post |
^ehe
yeah 10/30/2005 9:45:59 PM |
wildfaery Veteran 165 Posts user info edit post |
alright, I'll try that too and let you know if I come up with anything, it's doubtful though 10/30/2005 9:48:04 PM |
wildfaery Veteran 165 Posts user info edit post |
Ok, so we've got an extension for the homework with some hints for number two. I used the C-C eq to obtain P2 and then used PV=nRT to obtain V/n in L/mol. I'm not sure where to go from there in order to obtain kilograms. Any help would be appreciated. 11/1/2005 2:27:45 PM |
wildfaery Veteran 165 Posts user info edit post |
I need some help for 2 . . . . 11/1/2005 6:25:42 PM |
layuplilley New Recruit 44 Posts user info edit post |
I am in the same boat. i only have 1 and 4, and i am not even 100% sure i have them right. any help on 2,3, or 5 would be great, and get me one step closer to passing. thanks 11/1/2005 8:30:38 PM |
wildfaery Veteran 165 Posts user info edit post |
for 3 you have to find p2 using the clapeyron eq, but before you have to find the delta V, the eq. for it is in our notes: molecular weight/density - molecular weight/density.
for 5 I had to look in the book, I recommend pg 243 11/1/2005 8:52:49 PM |
Erfdawg All American 875 Posts user info edit post |
I don't see how you could answer #5 with the formula on pg. 243 11/1/2005 10:06:32 PM |
Erfdawg All American 875 Posts user info edit post |
Oh I got it nevermind yeah pg. 243 has the answer! 11/1/2005 10:09:18 PM |
Erfdawg All American 875 Posts user info edit post |
http://www.chem.queensu.ca/people/faculty/mombourquette/FirstYrChem/colligative/
scroll down this page for a worked example similar to #4 11/1/2005 10:57:51 PM |
layuplilley New Recruit 44 Posts user info edit post |
thanks for the help. i am gonna stare at #2 for a little while longer, and will let you know if i have any ideas, which means i will prob just see yall in class. 11/2/2005 12:48:11 AM |