Chem OCR unifying concepts revision!!!

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CogitoErgoSum

ahh! that helps a lot!
thank you!!

dont know about my chances for the exam tomorrow, though!!

Just do all the past papers and hope it's similar questions! For me it's like I know the formulas etc now but will I *still* know them by tomorrow afternoon.. I wish it was a morning exam!

But good luck anyway :smile:

Reply 21

Jen05

dont know about my chances for the exam tomorrow, though!!

Now you understand how that question works, you'll be able to do all similar questions. I got stuck on that same question when I did it as a mock, but now I understand that question, I understand so many more! Good luck :smile:

Reply 22

jayrox

Jen05

yup! thats true! mocks are good help for actual exams! im thinking it being afternoon helps in a way!

morning cram :biggrin:

Reply 23

Jen05

morning cram

Yep! Definately a good idea. I'm being way too relaxed tonight considering I've got 2 exams tomorrow. But I keep thinking, I've got the whole morning, may as well relax tonight! Hmmmm, maybe I should do something...

Reply 24

jayrox

Jen05

yep! im kinda like that! trying not to be and looking at papers.. but grrr lol! hard! maybe you should like.. check ya pms hehe :p:

Reply 25

lisaf6288

froggymills

Anyone sitting Chains, Rings and Spectroscopy? Im resiting it from January

yeh me 2, dunno why cos i scraped a B. i was under the deluded impression last results day that i could somehow get an A!!!! im a fool. i dying majorily with uni concepts revision

Reply 26

tishysquishy

Good luck to all ye chemists, may the (van der waals) force(s) be with u!
....oh dear that was bad
.... exam dementia has set in again :s-smilie:

..... we shall go down fighting til the bitter end! lol :biggrin:

Reply 27

violet

tishysquishy

Good luck to all ye chemists, may the (van der waals) force(s) be with u!
....oh dear that was bad
.... exam dementia has set in again :s-smilie:

..... we shall go down fighting til the bitter end! lol :biggrin:

Someone's had chemistry revision overload..! :p:

Reply 28

froggymills

Good luck everyone today

Reply 29

jayrox

violet

Someone's had chemistry revision overload..! :p:

lol!! just a lil :biggrin:

Reply 30

lisaf6288

everyones soo relaxed, im so doomed 4 this exam. havent had time 2 revise and i really really dont understand Buffer Sol's and some calculations. :frown:

good luck everyone else tho!!!

Reply 31

Pete.S

teacher predicts theres gonna be a essay on buffer solutions
the jan 05 paper was quite tough, hopefully this one will be easier, good luck to all

Reply 32

zaaks786

gud luck everyone :smile:

...im tryin to do a last min cram revision session!!!!

can anyone send me the jan 05 paper cos i swear i dnt hve it!!!!

Reply 33

almalm

zaaks786

gud luck everyone :smile:

...im tryin to do a last min cram revision session!!!!

can anyone send me the jan 05 paper cos i swear i dnt hve it!!!!

http://www.emailed.org.uk/

Reply 34

Cirsium

BUFFER SOLUTIONS?!?! OH **** i thought that was Unit 5?!?! *panics* AAAAAAARGH!! Someone tell me about buffer solutions

Reply 35

almalm

Bekaboo

BUFFER SOLUTIONS?!?! OH **** i thought that was Unit 5?!?! *panics* AAAAAAARGH!! Someone tell me about buffer solutions

wel buffer solutions resist small changes in ph on the addition of small amounts of acid/alkali.
They are made up of a weak acid and its sodium salt,

e.g. Ethanoic acid and sodium ethanoate.

CH3COOH ----> Ch3COO- + H+

When you add an acid, it reacts with the CH3COO- , and removes any H+ ions, thus maintaning pH.....when you add alkali, it reacts with the H+....remving the OH-.

Thats basicaly it....you find them in the blood, soaps, baby lotion....