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Thoughts on CSSA chemistry? (2 Viewers)

LMoura

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I heard the industrial chem questions threw a bit of people off? What are your thoughts on that? And also what did most people write for that Davy question?
 

ocatal

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I heard the industrial chem questions threw a bit of people off? What are your thoughts on that? And also what did most people write for that Davy question?
I spent way too much time on the two 6 mark questions for Industrial and ended up having to guess a few multiple choice questions because of it.
 

Siddy123

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what did u guys get for the mass of the the other thing? ( cant remember the question exactly but 2 of the others were 500g and they gave us the mm of each one)
 

LMoura

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what were the two questions again? Sorry i forgot them. And mc was decent however time was tight due to the extended response/ short answer questions.
 

LMoura

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I spent way too much time on the two 6 mark questions for Industrial and ended up having to guess a few multiple choice questions because of it.
what were the two questions again? Sorry i forgot them. And mc was decent however time was tight due to the extended response/ short answer questions.
 

Streetboy

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how did every find the question on the account the ph, something like 0.5?

Did you have to minus the two numbers to get 0.5, say why. ( I think it was 3 marks).
 

BabzBrah

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How'd use all go on the long response questions, I think I went ok.
 

mac1996

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how did every find the question on the account the ph, something like 0.5?

Did you have to minus the two numbers to get 0.5, say why. ( I think it was 3 marks).
oh i just said, its because of the large difference in volumes of the water and acid (was talking shit)
then i said it was also coz ethanoic acid is a weak acid, so on so.
 

Siddy123

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how did every find the question on the account the ph, something like 0.5?

Did you have to minus the two numbers to get 0.5, say why. ( I think it was 3 marks).
i wroe that she based it on the original volume (100mls) so when u added the 10ml it became 110ml and then u do it for that.
then did c1v1 before= c1v1 after and found the new conc
and took -log turned out to be whatevs she wanted so yeh
 

Siddy123

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What was the pH question? Interested.
a bitch found the pH of a 100ml solution
she added 10ml of water
she expected that her pH would drop by 1 unit but it dropped by 0.5
explain why etc etc

something like that^^^
 

mac1996

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i wroe that she based it on the original volume (100mls) so when u added the 10ml it became 110ml and then u do it for that.
then did c1v1 before= c1v1 after and found the new conc
and took -log turned out to be whatevs she wanted so yeh
bro i think ur right
i never thought of that in the exam
i just hope i dont move down too many ranks :s
 

sabrelord3

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What were the industrial questions about? I heard they were pretty hard
 

JBee

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i wroe that she based it on the original volume (100mls) so when u added the 10ml it became 110ml and then u do it for that.
then did c1v1 before= c1v1 after and found the new conc
and took -log turned out to be whatevs she wanted so yeh
The pH change was less than she thought because when we calculate pH with -log[H+] we're assuming that the acid fully ionises... but as you know ethanoic acid is weak (doesn't fully ionise in sol'n) so she'd need to calculate the degree of ionisation before she could calculate the pH
 

pscecelia

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multiple choice was soooooo tough! forensics amino acids..woooppss didn't study that. the short response was pretty good :D

what marks are you guys aiming for? I'm hoping a 70% plsssssssss
 

mac1996

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multiple choice was soooooo tough! forensics amino acids..woooppss didn't study that. the short response was pretty good :D

what marks are you guys aiming for? I'm hoping a 70% plsssssssss
yeah ill be happy with 70
but im not confident with my answers, so i might end up getting really shit
 

Siddy123

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The pH change was less than she thought because when we calculate pH with -log[H+] we're assuming that the acid fully ionises... but as you know ethanoic acid is weak (doesn't fully ionise in sol'n) so she'd need to calculate the degree of ionisation before she could calculate the pH
shit. ur right.
i forgot to calculate it and prove it ( though i mentioned it in my first line i think). :(
 

JBee

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multiple choice was soooooo tough! forensics amino acids..woooppss didn't study that. the short response was pretty good :D

what marks are you guys aiming for? I'm hoping a 70% plsssssssss
I'll be happy with 80%, but I'd rather 88+ because that's what i got in half yearlies :/
 

bfoo

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The pH change was less than she thought because when we calculate pH with -log[H+] we're assuming that the acid fully ionises... but as you know ethanoic acid is weak (doesn't fully ionise in sol'n) so she'd need to calculate the degree of ionisation before she could calculate the pH
yer this is what i wrote
 

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