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Dehydration of Ethanol (1 Viewer)

nit

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depends what ed of Mcmurry you've got. I've got the full 5th edition. Its in chapter 11, page413 roughly.
 

mitochondria

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shannonm said:
e1,e2,sn1,sn2 reactions are even in the hsc syllabus?
Yup, you're right, it's not in the HSC syllabus but it never hurts to know more :)



Nit:
Thank you again :) but I went "ooooh... cr*p" (Piper from Charmed in the excalibur episode) when I found out that mine it's a 6th edition.. looks like I have got some reading to do with this headache =x but yes, thank you again :)
 

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mitochondria said:
Yup, you're right, it's not in the HSC syllabus but it never hurts to know more :)
thank god for that

mito i see adv chem at new south in your sig. you are a brave soul my friend



nit, it looks like i stand corrected
 

mitochondria

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shannonm said:
thank god for that

mito i see adv chem at new south in your sig. you are a brave soul my friend
It's actually not much different to BSc. for the time being the only differences I know are:

1. there are compulsory courses other than those specified in the BSc. program
2. it leads directly to an honour year if you achieve an average of over 65 for each session

Besides.. I still suck at it =) personally I think getting a uai of 96 or below isn't hard at all (provided that you have the right subjects.. and you do study)... not a brave soul =x


And did I miss something? :


shannonm said:
nit, it looks like i stand corrected
 

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Catalysts are often used because of cost. Heat speeds up reactions but is expensive so catalysts are used instead. Also, many reactions would otherwise takes years to complete.
 

mitochondria

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shannonm said:
yeah wait for 3rd year phys anal and organ :D
well... I just love it..



gloria_b said:
Catalysts are often used because of cost. Heat speeds up reactions but is expensive so catalysts are used instead. Also, many reactions would otherwise takes years to complete
I'm not sure if that's an entirely right thing to say about catalysts.. If it's about cost then the whole process will be taken into account - I imagine that might be some expensive catalysts that are desingned solely for lowering the required the starting energy of a reaction and do not take costs into account..

Also heat does not necessarily speed up reaction.. I think (I have an extrememly crappie memory..) the Haber process is an example where lower temperature is more favourable since the production of ammonia from its elemental components is an exothermic process.. (apply Le Chatlier's principle).

It's not quite correct to say that catalysts are used instead of heat because, as I have mentioned above, catalysts lower the required energy for certain reactions..
 

nit

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Firstly, Gloria, Catalysts are pretty expensive, and aren't used as a replacement for heat. Both are required. If you look at the posts above, you'll notice that catalysts are required from a mechanistic point of view. They basically allow the reaction to occur via a pathway whose activation energy is lower, thus speeding up the rate of reaction. In this case, however many years you left your ethanol, it wont be converted into ethene unless the conditions are right...again, I refer you to the posts above.

Mitochondria: heat always speeds up the rate of a reaction - it means more molecules with sufficient activation energies collide to form the products. The problem in the Haber Process is that that process is exothermic. Thus the heat will, while affecting the kinetics, nonetheless affect the thermodynamics of the reaction - ie itll push the equilibrium to the left, thus decreasing ammonia yield. At the same time however, it is increasing reaction rate, due to the reasons stated above.

Edit: hmm, what are you guys doing in anal chem atm or in the future? I always hated that.
 
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mitochondria

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nit said:
Mitochondria: heat always speeds up the rate of a reaction - it means more molecules with sufficient activation energies collide to form the products. The problem in the Haber Process is that that process is exothermic. Thus the heat will, while affecting the kinetics, nonetheless affect the thermodynamics of the reaction - ie itll push the equilibrium to the left, thus decreasing ammonia yield. At the same time however, it is increasing reaction rate, due to the reasons stated above.

Edit: hmm, what are you guys doing in anal chem atm or in the future? I always hated that.
arrrg... omgeeez x______X I had that in mind before I posted and forgot about it and let the stupid process took over (wait.. not supid.. fun things to do with ammonia..) I did did did did did have that in mind and I was going to say it.. *sigh.. very embarrassing* thannks for the correction though... =x

blames headache...

I did have that in mind...

oh nitty, did you do the Chem olympiad thingy?
 

nit

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yes, I did chem olympiad- international team '04

oh, please don't fiddle around with my username...please :eek:
 

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nit said:
Edit: hmm, what are you guys doing in anal chem atm or in the future? I always hated that.
anal chem is aas, liq chromatography, mass spectroscopy, flow methods and a bit of electrochem (fancy name = voltommetry, or something along those lines)
 

mitochondria

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nit said:
yes, I did chem olympiad- international team '04

oh, please don't fiddle around with my username...please :eek:
Fiddling wasn't exactly the word to describe it.. but alrighty =x no fiddling.. (seriously, that sounded better...) *throws tonnes of apology on top of nit*

I did have that in mind... =x mixed up with yield the moment I typed it *frown* oh well... what's done is done...

finds more excuses.. yes.. I have been reading the whole day so allow me one mistake ^________^

anyways.. time for bed and enough spamming..take care everyone xD sweet dreams.. ciao!
 
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nit

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what about equilibrium and equilibrium calculations? Ka's, Kd's, Kf's, Ksp's etc..?

i guess theres a lot of nernst bashing as well.
 

mitochondria

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nit said:
I think this thread has outlived its usefulness....
The old me..

Reminder: it takes more than oneperson to do it..


make it my last post on this thread..
 

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