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OCR AS - Chemistry Unit F322 - Chains, energy and resource - REVISION!

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Ethyl Propanoate

Original post by RedDevilThing

What about that question on international cooperation? That was pointless.

Also I really couldn't think of another use of methanol. :angry:

I wrote feedstock for cracking :s-smilie:

Reply 662

Joseppea

Original post by nereik6794

-1000 and something

Same

Reply 663

ChessMister

Original post by bubblebuddy

What do CO and HCl do to the environment?

HCL- stratosphere- Cl radicals etc.

Reply 664

Joseppea

Original post by nereik6794

I wrote feedstock for cracking :s-smilie:

Methylated Spirits :cool:

.....but I just put "spirits" XD

Reply 665

Joseppea

Original post by ChessMister

Ethyl Propanoate

Damn! I put ethyl ethanoate as it's the only ester we've ever talked about :colondollar:

Should get marks for working it all out though :colone:

Reply 666

racheatworld

Original post by 786girl

what about the equilibrium question..can...rate of forward etc
wth was that about?

altho most of it was alright i guess, i got propyl propanoate ! i drew it wrong so i guess thats about 3-4 marks down...

q about international cooperation lmao

also for the hess cycle did u have to draw it arrows going down or up?? coz it asked for formation but values were combustion?! i went for combustion in the end

Equilibrium was asking you why it took shorter time for the reaction to get into a dynamic equilibrium with pressure increase. Basically, this was rate of reaction increasing, more particles per unit volume, more frequent collisions etc.
Then it also said why does the composition not change of the mixture? This is because increase in pressure favours the side with the least gaseous moles, in the equation both sides has equal number of gaseous moles (both had 2) so position of equilibrium did not change, no NET effect on composition.

I know, I didn't like the international co-operation, talked about how if all countries don't co-operation pollution will continue, example using CFC's and how developing countries still use them, then talked about Montreal and Kyoto agreements.

Reply 667

EternalDoom

Original post by Joseppea

Methylated Spirits :cool:

.....but I just put "spirits" XD

I put methylated spirits, but people said thats the same as a solvent? Spec only says methanol as solvent and fuel, so wtf else is it used for ?

Reply 668

nereik6794

Original post by Joseppea

Methylated Spirits :cool:

.....but I just put "spirits" XD

I was going to write that but I thought methylated spirits are solvents? :s-smilie:

For the percentage yield of ethanol I was tempted to write something like 'More alcohol for fun' haha. Obviously I made up something chemistry related :tongue:

Reply 669

RedDevilThing

Original post by Joseppea

Methylated Spirits :cool:

.....but I just put "spirits" XD

Isn't that just a solvent though, like it mentioned in the question?

Reply 670

anil10100

Im gonna try to recreate the paper:

1. Define enthalpy change of combustion.
Calculate enthalpy change of formation from enthalpy change of combustion: 6C + 6H2 + 02 -----> C6H12O6
The equation for the respiration for glucose, is the same as the equation for the combustion of glucose, what is it?

2. Something about N2 + O2 ----> 2NO
If these two gases are kept in a container for a day under constant heat, how do they eventually reach dynamic equilibrium? You must refer to the forward and backward reaction?
If high pressure is added, explain why the rate of reaction increases, and why the final concentration of products remains the same?
In a car engine, why is dynamic equilbrium never reached?

Err yeah, if anyones got the answers reply

Reply 671

racheatworld

Original post by Joseppea

Methylated Spirits :cool:

.....but I just put "spirits" XD

I thought it said other than a solvent? Or did it not... :confused:

Reply 672

shuty

Original post by anil10100

Anyone want to join me to hunt the chief examiner and poison him with carbon monoxide?

Im with u all the way mate :biggrin:

Reply 673

Joseppea

Original post by RedDevilThing

Isn't that just a solvent though, like it mentioned in the question?

Ah............well there goes my mark. xD

Reply 674

Nkhan

formation question was -1239

Reply 675

user152713

Easy paper, just forgot about tetrahedral :/
Boundaries should be around 74 for an A.

Reply 676

timkench

whats better, high percentage yield or atom economy?

Reply 677

Joseppea

.................hydrolysis is nucleophilic substitution right? O_O

Reply 678

Yarpie

I don't think there will be marks for naming the compounds X, Y and Z. Only for finding the structural formula. For those types of questions they usually say ignore names.