!! LC Chemistry '16 HL - Before and after ...

lc16_

Hows everyone set for Chemistry?

Knowing its my last exam is clearly not helping me focus for the evening in any way shape or form

alaandocs

lc16_ wrote: »

Hows everyone set for Chemistry?

Knowing its my last exam is clearly not helping me focus for the evening in any way shape or form

Should be good to go, experiments are where I'm focusing atm

juniorcert

lc16_ wrote: »

Hows everyone set for Chemistry?

Knowing its my last exam is clearly not helping me focus for the evening in any way shape or form

Same, I'm finding it very hard to concentrate or to care very much anymore when I know freedom is so close

Seaaan

The fact that it's in the afternoon leaves me thinking I can put off cramming until tomorrow. Bad idea I think

lc16_

Seaaan wrote: »

The fact that it's in the afternoon leaves me thinking I can put off cramming until tomorrow. Bad idea I think

^^^Exactly what my mind is playing at currently

Seaaan

They better not spring surprises on us for this either; physics had them! Iron tablets and Ethene/Ethyne please.

WorthlessPeon

Seaaan wrote: »

They better not spring surprises on us for this either; physics had them! Iron tablets and Ethene/Ethyne please.

Ideal experiments right there, throw in the relative atomic mass of a volatile liquid one and we're away!

emersyn

If ethene/ethyne comes up I'll cry with joy

louisoc

Anyone else given phenylmethanol the slip? I know it's irresponsible to avoid things, but I just can't hack that experiment - it didn't work when we did it in class, and the minutiae of the procedure are unbearable. Feeling adventurous completely ignoring it, but I'm confident with my titrations and the other miscellaneous experiments.

LordHypnos

louisoc wrote: »

Anyone else given phenylmethanol the slip? I know it's irresponsible to avoid things, but I just can't hack that experiment - it didn't work when we did it in class, and the minutiae of the procedure are unbearable. Feeling adventurous completely ignoring it, but I'm confident with my titrations and the other miscellaneous experiments.

absolutely, willing to take that chance

DownOneTourist

LordHypnos wrote: »

absolutely, willing to take that chance

it's quite embarrassing but after 2 years of chem I have no idea what you two are talking about. I'd better sort that out. perhaps tomorrow morning

LordHypnos

DownOneTourist wrote: »

it's quite embarrassing but after 2 years of chem I have no idea what you two are talking about. I'd better sort that out. perhaps tomorrow morning

it's the mandatory experiment they added for last year's exam.
here's a full list of updates to the course;
http://www.gilleducation.ie/AcuCustom/Sitename/DAM/060/LSMS_Chemistry_Changes_to_the_Experimental_Work.pdf

DownOneTourist

LordHypnos wrote: »

it's the mandatory experiment they added for last year's exam.
here's a full list of updates to the course;
http://www.gilleducation.ie/AcuCustom/Sitename/DAM/060/LSMS_Chemistry_Changes_to_the_Experimental_Work.pdf

it actually rings a bell now. thanks for the link. I remember aqueous layer and organic layer.

louisoc

DownOneTourist wrote: »

it actually rings a bell now. thanks for the link. I remember aqueous layer and organic layer.

aqueous and organic layer are a new part of the clove oil experiment, not the phenylmethanol. I'd say THAT one is definitely worth knowing, given that I think it's the only thing on the entire course right now that's never been examined!

hurler97

louisoc wrote:

Anyone else given phenylmethanol the slip? I know it's irresponsible to avoid things, but I just can't hack that experiment - it didn't work when we did it in class, and the minutiae of the procedure are unbearable. Feeling adventurous completely ignoring it, but I'm confident with my titrations and the other miscellaneous experiments.

We referred to it as the benzoic acid experiment so maybe other people who don't recognise phenylmethanol will know what the experiment is now

Misty_01

Can any one explain the 2015 Q11 B to me , the part where it asks if the reaction is exo or endothermic ???? Thanks.

daraghwal

Does anyone have a list of the experiments that come up in question 1 and 2? I know 1 is vol analysis and 2 is organic but I'm just not sure which ones they can potentially ask. Also is it alright to leave out electrochemistry? Just have a look over it maybe?

louisoc

Misty_01 wrote: »

Can any one explain the 2015 Q11 B to me , the part where it asks if the reaction is exo or endothermic ???? Thanks.

From the graph you can see that the Kc rises exponentially as temperature increases, that means that as Kc increases, the left side becomes less concentrated and the right side becomes more concentrated. (because Kc is right side over left side, if denominator is smaller and the numerator is bigger the number is bigger). Temperature increase always drives the endothermic reaction (to counteract stress; Le Chatelier's) which means the forward reaction - the dissociation of gas A - is endothermic.

Bangdiggy

Misty_01 wrote: »

Can any one explain the 2015 Q11 B to me , the part where it asks if the reaction is exo or endothermic ???? Thanks.[/quote
From the graph you can see that Kc increases as temperature increases. And you should know that an increase in temperature always favours the endothermic reaction. Now if you look at the equation you see that if the top is exothermic and you ↑temp then the the bottom(backward) reaction is endothermic BUT... it says the dissociation of A, therefore if bottom(reverse) is endothermic then that means your making A and not dissociating it, So then that means the top(forward) reaction will be Endothermic

Oh dear, I don't think I would understand myself, so I hope you understand

lc16_

Q1) Iron Tablets exp
Q2) Ethene/Ethyne
Q3) Rates of reaction exp
Q4) Short qs heavily on defintions
Q5) Trends in periodic table & bonding
Q6) Thermochemistry equations & Fuels, hydrocarbon definitions
Q7) Long water q
...Q11) A- Gas laws & calculations
B- Equilibrium defs & calc
That would be an absolute beauty of a paper

LordHypnos

lc16_ wrote: »

Q1) Iron Tablets exp
Q2) Ethene/Ethyne
Q3) Rates of reaction exp
Q4) Short qs heavily on defintions
Q5) Trends in periodic table & bonding
Q6) Thermochemistry equations & Fuels, hydrocarbon definitions
Q7) Long water q
...Q11) A- Gas laws & calculations
B- Equilibrium defs & calc
That would be an absolute beauty of a paper

I'll put a word out

Seaaan

Acids and bases please. And a not rotten Q8; Esters I'm looking at you.

Perhaps radiation because Chernobyl anniversary!?

Ufc2016

I hope it's not a paper like last years!

alaandocs

That was an awful question 2 they put I thought. Apart from that it's was generally ok, going for an A1 but if say it will be close

Seaaan

Q1 was meh. Q4 lovely, Q4 lovely, 5 lovely, 6 lovely, 11 lovely and 10 wasn't bad either.

Equilibrium constant answer, anyone? I got 78.4

BrownTrout

Seaaan wrote:

Equilibrium constant answer, anyone? I got 78.4

Lol 39something000

medhopeful16

Seaaan wrote: »

Q1 was meh. Q4 lovely, Q4 lovely, 5 lovely, 6 lovely, 11 lovely and 10 wasn't bad either.

Equilibrium constant answer, anyone? I got 78.4

Think I got that too

medhopeful16

Q2 and Q5 were not great but the rest of it was amazing, couldn't have asked fir a better paper. No electrochemistry and straightforward organic questions

DownOneTourist

Q3 was my jam! Anyone get 10cm3 per minute?
I went in hoping for a b3 but I think I got a b1! Time will tell

medhopeful16

DownOneTourist wrote: »

Q3 was my jam! Anyone get 10cm3 per minute?
I went in hoping for a b3 but I think I got a b1! Time will tell

I got 8.9 I think but close enough!