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jonnyofengland

Glad to see other people share my dread of buffer solutions.

I don't suppose anyone who is good with them would be able to explain them to me?

http://www.docbrown.info/page07/equilibria6.htm - that's good a good-ish section on them, you have to scroll down though

http://www.chemguide.co.uk/physical/acidbaseeqia/buffers.html#top

Hope they help :smile:

Wait...

jonnyofengland

Glad to see other people share my dread of buffer solutions.

I don't suppose anyone who is good with them would be able to explain them to me?

You got a weak acid and it's sodium salt.

e.g. CH3COOH and CH3COONA

The weak acid partially dissociates so you have loads of CH3COOH
The sodium salt almost fully dissociates so you have loads of methyl carboxylate ions (and sodium ions). This is your buffer.

Adding Acid

The H+ ions from the acid reacts with the methyl carboxylate ions forming ethanoic acid. Most of the H+ ions are removed so pH returns to normal.

Addid Base

The OH- ions react with the ethanoic acid to produce methyl carboxylate ions and water. Most of the OH- ions are removed so pH returns to normal.

- This only works for a limited volume of acid/base added until it overcomes the solution and the buffer doesn't work.

Hope this helps :smile:

Reply 3943

Phalanges

Thanks Scaryhair and Daniel! :top2:

ADREAM

All you've got left? I thought that was the main bed-rock behind Unit 4 Chem, no? :p:

I hate the inorganic chemistry with a passion though. :yep:

pH, buffer solutions, all that k-stuff - just urgh! Shame it was the main focus on one of my Ox interviews! :frown:

Well, what I mean is that I understand pretty much all of the theory, now it's just committing various temperatures, catalysts and effervescences to memory.

Reply 3944

ADREAM

jonnyofengland

Thanks Scaryhair and Daniel! :top2:

Well, what I mean is that I understand pretty much all of the theory, now it's just committing various temperatures, catalysts and effervescences to memory.

Ah, I see... Good luck!

Reply 3945

i'm no superman

lotusx

@!MEna: BYB4 may have more topics in, but BYB5 is a load of nonsense...damn ecology!

Yeah you can say that again.

I've just been reading up on classification and this is how I've learned the hierarchy...

Kate
Perry
Can
Order
Flaming
Grilled
Steak

Kingdom
Phylum
Class
Order
Family
Genus
Species

Anyone else using acronyms to help with revision? :toofunny:

Reply 3946

scaryhair

!MEna

Got a better one than that...
King
Phillip
Comes
Over
For
Good
Sex

:p:

Reply 3947

i'm no superman

scaryhair

Got a better one than that...
King
Phillip
Comes
Over
For
Good
Sex

:p:

Haha now that will be stuck in my head! Cheers! :rofl:

Reply 3948

Make_It

I'm get to start revision :s-smilie:

Tomorrow shall be the day.
I seriously have to get started.
I don't know anyone that hasn't started revision yet :s-smilie:

But I do only have BYB4 and C3 - not so much compared to others.

!MEna

There was a question in my CPT4 mock and it was "What is a thread?" You will not believe the answer I put. :ninja:

What did you put? I wanna know :biggrin:

Reply 3949

Holsy

scaryhair

Got a better one than that...
King
Phillip
Comes
Over
For
Good
Sex

:p:

Ahha that's brilliant. Thank you. :grin:

Reply 3950

scaryhair

!MEna

Haha now that will be stuck in my head! Cheers! :rofl:

Holsy

Ahha that's brilliant. Thank you. :grin:

Lol, don't thank me, thank one of my Biology teachers! She's brilliant! Tiny, innocent looking thing and then her cover is blown when she comes out with stuff like this :p:

Reply 3951

Sanjetti

scaryhair

Lol, don't thank me, thank one of my Biology teachers! She's brilliant! Tiny, innocent looking thing and then her cover is blown when she comes out with stuff like this :p:

It's way better than my one! I shall be using this haha :biggrin:

Reply 3952

ADREAM

scaryhair

Lol, don't thank me, thank one of my Biology teachers! She's brilliant! Tiny, innocent looking thing and then her cover is blown when she comes out with stuff like this :p:

Hahaha! You sure have one interesting teacher!

Reply 3953

scaryhair

ADREAM

Hahaha! You sure have one interesting teacher!

She's quite mad, yes. Once she walked out of the classroom to get some past papers, and in an ordinary voice warned us not to eat any old people!
She's great though :smile:

Reply 3954

ADREAM

scaryhair

She's quite mad, yes. Once she walked out of the classroom to get some past papers, and in an ordinary voice warned us not to eat any old people!
She's great though :smile:

Haha!

My biology teacher, sorry ma'am if you're reading this, is even worse. She doesn't understand the syllabus at all. I mean, when we go through mark schemes, she refuses to accept it in almost every circumstance, even when we tell her 'No, Miss - you do X and Y, not Z.'

She leaves our lessons to go and eat food, constantly. Being honest here! :yep:

There was one time where she refused that there still was three quarters of an hour till lunch, so she got a ladder and fast-forwarded the clock to lunch-time and let us all go. Sometimes it borders on the insane, but still - we love her! :yep:

Reply 3955

Kelly^2

King
Prawn
Curry
Or
Fat
Greasy
Sausages

Reply 3956

shahrukh24

we were always told

King
Phillip
Came
Over
For
Gold &
Silver

Spanish armada or something? I think i'll remember the 'good sex' one better though

Reply 3957

Holsy

I've been having fun with organic synthesis on my new white board off ebay!

Feel free to use it for revision and if there are any errors or additions don't hesitate to let me know. :grin: