Chemistry aftermath

cson

It was pretty predictable overall though, I mean Ethanoic, Thiosulfate, Heat Neutralisation...

cocoa

lolz, you know a forum kicks ass when rebuttals are made for you

it was definitely a nice paper, and though I prob made slips here or there, I'm still quite certain of my A1

Shox

Does anyone know the answer for the last bit of the water an acid question where they asked what removes large metal ions from water in big quantites.. The question before was takin about eutriphocation, so i presumed twas one of the sewerage practises.. i guess primary (prob wrong)

But then my friend said usin an ion exchange resin which makes sense removing calcium and magnesium! Tout twas very confusin seen as dey din say water treatment!!

Gangsta

ah crap i messed up the q1 and q2 calculation!

for q1 i mixed up the volumes, is that -6?
and for q3 i multiplied 420 by 0.1, is that -6 also?

What did people write for q2(c)? Ah sh!te this rate I'm going to get an a2:(

eZe^

cocoa wrote:

oh yeah, i just kind of asumed they were giving standard temp and pressure...uh oh.. *checks*
hmm, i get 1.08l when i do it that way... I must be doing something wrong because that would be astonishingly unimpressive to say the least...

Did you maybe think the SI unit for volume was litres instead of m^3? Because thats what I got?

Gangsta

eZe^ wrote:

Did you maybe think the SI unit for volume was litres instead of m^3? Because thats what I got?

SI unit for volume is m^3

JC 2K3

Shox wrote:

Does anyone know the answer for the last bit of the water an acid question where they asked what removes large metal ions from water in big quantites.. The question before was takin about eutriphocation, so i presumed twas one of the sewerage practises.. i guess primary (prob wrong)

But then my friend said usin an ion exchange resin which makes sense removing calcium and magnesium! Tout twas very confusin seen as dey din say water treatment!!

You remove heavy metals by precipitation.

eZe^

Gangsta wrote:

SI unit for volume is m^3

Thats what I said...I was suggesting maybe when he found the volume he labelled the answer 1.08L instead of m^3.

cocoa

eZe^ wrote:

Thats what I said...I was suggesting maybe when he found the volume he labelled the answer 1.08L instead of m^3.

you're correct, but it was said earlier in the thread already ...

Thomas_S_Hunterson

cocoa wrote:

if there's no need of a per-mole then why did you divide by 0.05? (the amount of moles of HCL, and coincidentally of NaOH)

420*6.7/0.05=56280J/mole=5628kJ/mole

Because the Chemical equation given specifies that one mole of HCl and NaOH react.

JC 2K3

Yeah but the unit of heat of reaction is kJ mol^-1 and they asked for the heat of reaction here, not the heat released during this specific reaction.

cocoa

sean_keevey wrote:

Because the Chemical equation given specifies that one mole of HCl and NaOH react.

exactly, so you are giving the heat per mole...

Gangsta

it's kj.mol^-1

But I left it in joules another -3

ah that was a terrible twist to what should have been a very straight forward question.

sxcbbz

i dint do chemestry!! soz hunis!!

XxXxXxMwAhXxXxXxLoVsYaXxXxXxBeXyXxXxXx

cson

You obviously didn't do english either.

HungryJoey

sxcbbz wrote:

i dint do chemestry!! soz hunis!!

XxXxXxMwAhXxXxXxLoVsYaXxXxXxBeXyXxXxXx

What the ??

I've seen that sh*t all over the leaving cert section.

sxcbbz try this one http://bebo.com :rolleyes: ( Yes, thats right.. you CLICK it ) .. Sorry couldn't resist!

Hj

remus808

Anyone else leave at half three? (Honours)

..I even did 10 questions...