Industrial Chem: Equilibrium (1 Viewer)

[-=«MÄLÅÇhïtÊ»=-]

What equilibrium did u do?

I did the N2O4<>2NO2 one, but it took me ages to remember it. All I could recall wen i was browsing thru my book was NO2 on RHS, so i ended up tryn to work out wat was on the LHS.

It asked for qualitative analysis, so i spoke about colour changes due to pressure and temp. I almost 4got about this. During reading time i was planning to do the one where u remove 10mL from 1 beaker and 5mL from other beaker and continue until u get an equilibrium, but that wasn't really qualitative.

I juz thought it was a biatch they asked that ques, coz it's not liek sumfin u'd do at skool. I was hoping for the solvay process.

 

[doctor]

yeah i fucked that one up. i didnt even use an equation
ill get zero for that part

 

[Ozz^E]

This was prob the only question in the whole test that needed thought. Only coz i didnt focus on any of the equlibrium exp. but i think i handled it pretty well in the end:

I thought of a number of equilibrium reactions but most were from the core topics not industrial and some were not doable in the lab...like ammonia prod. Then i remembered the CO2 H2CO3 equilibrium and i knew it really well but it was from topic 2. Luckily i figured a way to connect the two: The first step of SOLVAY process involves carbonating the brine where the CO2 + H20<>H2CO3 and so i said that we choose to understand qualitative equilibrium reactions by looking at this and then analysed pressure, temp changes on the equilibrium in part (ii). Dun know...hope i get most of the marks.

There werent any questions on the solvay process...

 

[RageAgainstBOS]

yeah i did the NO2 N204 one but i wrote N02 goes to NO3 i realised it when i left the exam room.....FUCKSHIT.........oh well.......how many marks could they take away for that? apart form that that was the easiest chem test ive done.......honestly.........same as physics i thik that was too easy........goddamit i wish bio was like that........it was fucked.....im still pissed at that..........oh well who cares...........THE HSC IS OVER FOR ME..........good luck to anyone who still has tests and i hope everones uais are good enuff and interviews or whathaveu go well!!

later all!

 

[gman]

yeah....that took me ages too

i used some obscure one we did in school
[Co(H2O)6]2+ + 2Cl- <> Co(H2O)4Cl2 + 2H2O

i dont know if theyll believe me anyway!

 

[-=AETOS=-]

I used the CO2> H2C03 equilibrium as i thought it was the easiest. I thought about doing NO2 but i couldnt remember exactly what we did.

 

[-=«MÄLÅÇhïtÊ»=-]

the co2<>carbonic acid 1 is pretty ez, but how were u able to analyse the qualitative aspects of it? Coz arent all the measurements quantitative?

Like i wanted to do that natural system carbonic acid <> salts from rocks near rivers and lakes equilibrium, but couldn't think of any qualitative aspects, like measuring salnity etc is quantative.

 

[-=AETOS=-]

Thats easy! I made up some bullcrap about pasing the gas evolved when you opened the bottle through lime water, indicating the presence of C02 which shows the change in equilibirum. Secondly I said that I used a 'One-Way Valve' to inject universal indicator to test the pH before the bottle was opened. Thus as the bottle is opened the colour of the pH becomes more neutral!

 

[Ozz^E]

The effects of changes in temp and pressure are qualitative. U could have used them.

 

[-=«MÄLÅÇhïtÊ»=-]

ah right...ph test
i guess u shoulda said u put the indicator in initially before u changed temp or pressure coz u dont really need a one way valve...if there is such a thing to contain gases..

i think i read a comment from last yr's hsc saying "some responses were too fanciful and obviously showed no experience in real experiements"

but that's the gay part of this ques, coz i doubt any1 wouldve done it properly at skool

 

[utopian731]

i jsut did small scale reflux without esterification in little test tubes

i remmeber we did that

its an equilibrium aint it?

 

[-=AETOS=-]

No I don't think esterification is equilibrium.......its just a very slow reaction

 

[utopian731]

nar it is



gday ziggy

 

[-=«MÄLÅÇhïtÊ»=-]

i dunno know much about how equilibrium relates to esterification...

but where's the reverse reaction in esterification? I thought after u heat reactants, the products stay as they are.

 

[-=AETOS=-]

yeh neither do i
cumon pietro explain the principle bro !

 

[utopian731]

Nar, im not talking about esterification with reflux. We did that to, but we also did it without heat by simply placing the reactants and sulfuric acid in small test tubes, which forms an equilibrium...

Even with reflux, the reverse reaction is still occuring, even though on a small scale, it is sitll there, expecially after allowing the mixture to kool....

 

[utopian731]

I admit, not the best of examples

but hey, its still technically right, if not for the full quota of marks, then at least for 3/4