The Student Room Group
Competition - post a photo you've taken of nature >>
Competition - post a photo you've taken of nature >>
Competition - post a photo you've taken of nature >>

Equilibria, Energetics and Elements (F325) - June 2011 Exam.

Scroll to see replies

Reply 1360
Avatar for Steven
Steven
4
Original post by Twinkles
Why does [Cu(H2O)6]2+ + HCl turn green first then yellow?


I think it's green when the concentrations of the 2 complex ions are equal, an equal amount of blue + yellow = green
Do we need to know haber process, contact process etc???????
The June 10 paper wasn't too bad I though. But the January 11 one was on a whole other level, I found it infinitely more difficult...
I'm hoping because its a June exam and most people are doing it for the first time it'll be easier, and to compensate for the massive cock-up they did in January for us...
Reply 1363
Avatar for susan23
susan23
3
Original post by jontylol
The June 10 paper wasn't too bad I though. But the January 11 one was on a whole other level, I found it infinitely more difficult...
I'm hoping because its a June exam and most people are doing it for the first time it'll be easier, and to compensate for the massive cock-up they did in January for us...


Yes I know tell me about the january 2011 is so hard...do you mind helping me with a question in that paper...i posted it on the previous page. I'd be so grateful!! If not...it's fine..
Original post by INeedToRevise
Do we need to know haber process, contact process etc???????


Just the catalysts for each. Iron for Haber, and vanadium (V) oxide for contact.
Original post by gregory14db
Just the catalysts for each. Iron for Haber, and vanadium (V) oxide for contact.


Thanks :smile:
Reply 1366
Avatar for Rob16
Rob16
Tomorrow is not going to be a fun day at all :frown: :frown:
pH of 0.015mol of acid is 1.82.

Nitric acid is diluted with equal volume of water.

How do you work out pH of diluted acid?
I'm taking an early night and signing off - good luck people, lets hope OCR doesn't **** up again.
For kstab you dont add liquid in the equation but what about kc?
How do we know if a reaction will actually take place?

how big does the standard electrod potential difference have to be?
Reply 1371
Avatar for Steven
Steven
4
Original post by INeedToRevise
pH of 0.015mol of acid is 1.82.

Nitric acid is diluted with equal volume of water.

How do you work out pH of diluted acid?


Since you are adding the same amount of water to the amount of nitric acid, the concentration of nitric acid halves. 0.015/2 = 0.0075

So the new pH = -log[0.0075] = 2.12
Original post by Pandit Bandit
How do we know if a reaction will actually take place?

how big does the standard electrod potential difference have to be?


differences have to be greater than 0.4V

Can u help me


pH of 0.015mol of acid is 1.82.

Nitric acid is diluted with equal volume of water.

How do you work out pH of diluted acid?
Original post by Ayostunner
For kstab you dont add liquid in the equation but what about kc?


Isn't that you dont add water??
What I want to see tomorrow:
Essay question on Transition metal complexes and stereo isomerism.
Long Electrode Potentials question
Long rate equation question

What i don't want to see tomorrow:
Essay question on buffer solutions
Long question on fuel cells
Anything to do with hairdressing
Reply 1375
Avatar for voices1
voices1
Original post by sportycricketer
Isn't that you dont add water??


its water. hAving said that, the conversations we had previously best to double check.:biggrin:
Original post by voices1
its water. hAving said that, the conversations we had previously best to double check.:biggrin:


Can you expand on this?
What don't we include into the Kstab equation?
Original post by jontylol
What I want to see tomorrow:
Essay question on Transition metal complexes and stereo isomerism.
Long Electrode Potentials question
Long rate equation question

What i don't want to see tomorrow:
Essay question on buffer solutions
Long question on fuel cells
Anything to do with hairdressing


1.

Buffers

2.

Transition Metals

3.

Rate Equation

4.

Born-Haber Cycle

5.

Electrode Potentials



These are almost guaranteed to come up. They have tested Fuel Cells in both papers, I really hope they dont come up!
Original post by Steven
Since you are adding the same amount of water to the amount of nitric acid, the concentration of nitric acid halves. 0.015/2 = 0.0075

So the new pH = -log[0.0075] = 2.12


Thanks. I always get confused with dilutions. It makes concentration smaller, i always forget.
Reply 1379
Avatar for susan23
susan23
3
Original post by Pandit Bandit
How do we know if a reaction will actually take place?

how big does the standard electrod potential difference have to be?


the larger the diff between E-standard the more likely the reaction will take place however if the diff is less than 0.4V then the reaction is less likely to take place :smile:

Quick Reply

Related discussions

Latest

Trending

Trending

Articles for you