Definitions and Things to Memorise for HL Chem

I know this is a bit (heh, JUST A BIT) late to be asking/confirming this... but I guess you could consider this revision. :redface:

What exactly do we need to memorise for chemistry (*thunder, lightning*)? I'm referring to things you just need to know off by heart, like definitions of certain terms like 'ligand', reactions of period three oxides and chlorides, and gas law formulae.

Obviously things like the Arrhenius equation will be in the data book, but are there any gas law formulae that aren't in there? And do we need to know ALL the oxidation states of transition metals? Etc etc.

Eek, I'm honestly dreading this exam muchos. I have a sneaky feeling that it'll be super hard this year, and full of little traps set for us by the lovely examiners. They're sadistic that way :smile:

Reply 1

afoneleri

the only things I can remember:

Know the different definitions of acid and base

know the different organic compound formulas.

mm...if i remember anything else, I'll let you know.

Reply 2

Sadie_F

be VERY CAREFUL with how much you rely on the data book as you cannot have it for paper one.
this is the scariest exam for me too... *SIGH*

anyway, handy equations include:
delta g = delta h - t delta s
Ka = x2/a-x (approx. x2/a) -> and the base equivalent, and the buffer equivalent (just that equation rearranged, basically)

which gas law formulae are you referring to exactly? i just spent all day yesterday revising acids and bases... i need to look up the gas laws now, thanks for reminding me
*SIGH* i hate chemistry so much. i don't even want to have anything to do with science in the future. my top choice university is berklee college of music. why oh why...

Reply 3

Sadie_F

i just saw afoneleri's post... which reminds me, the organic compounds are mucho important.
like, -yne meaning there's a triple bond, -ene meaning there's a double bond,
-ol meaning there's an OH, -oic acid meaning there's an OH and a double O.

also you may want to look at born haber cycles, cos those are easy to forget but take about 10 minutes to learn and can get you 6 points on a paper 2 section b.

EDIT: question, how do you define "hybridization"? i know about sp, sp2, sp3 etc, but is there a general definition? i couldnt find this in my book and a past paper asked for it... :-/

Reply 4

Mlzas

Learn how to calculate Ka/Kb. Learn how to calculate buffer concentrations. Learn the characteristics of transition metals. Learn the characterstics of period 3 oxides/chlorides. Learn a couple of oxidation numbers (Fe and Cu notably). Learn the process of how to balance redox equations. Learn organic reactions and functional groups. Learn definitions of molecularity, activitation energy, amphipoteric bla bla.. learn about catalysts. They LOVE catalysts! That said, I'm a bit confused with buffer calculations... and oh, learn the defintitions of different changes in enthalpy!

Reply 5

The_Luvbster

(Pst, Sadie, it's Kasia (again)! Hi! :biggrin:

)

Yeah, I'm thinking of compiling a list of ALL the definitions we just need to know off by heart. If I have time (and if I can be bothered, haha) I'll post them up here. Otherwise if anyone else can find the incentive and has strange urges to type up chemistry definitions, you can get us started :smile:

. Or is this a bad idea, considering there's tons of them?

And WHAT formulae were those?! The delta 'h' and delta 'a' ones... I've never even seen them in my life. Are you sure that's not something you learnt in your option topic?

Reply 6

girl-on-ice

Lol, without exaggeration, i just finished making lesson notes on all of chemistry. Because i had basically NOTHING from our teacher. Hmm.. the only problem now is to learn it... I am pretty certain I'm going to be up all night Thursday/Friday revising the options. Is that a really bad idea???

The only helpful hint I can give about memorising is to look at the syllabus and look for all the parts where it says DEFINE or STATE (eg. define acids and bases according to the Bronsted-Lowry theory OR state the Aufbau principle).

Dreading HL Chem exams like nothing else... :O
Good luck my fellow masochistic IBers!!!

Reply 7

Mlzas

I think by the delta "h" formulae, he/she are takling about the Gibbs' equation, which is a core topic!

Reply 8

Sadie_F

hahahahahahaha oh my, hey!

delta h is enthalpy change... the calculation for delta g is of free energy based on enthalpy and entropy, and it's very important.
as for catalysts, the main thing to learn about them (as well as the two specific examples for haber and contact) is that they don't affect the position of equilibrium - i can't tell you how many times i've seen them ask that!

zeyadleo's things to learn:
i know Fe goes to 2+ and 3+... what about Cu?
and as for the oxides (or is it the chlorides? :-/ ) it starts acidic and turns alkaline? is that correct?
aiee im scared

EDIT: girl-on-ice, whatever you do, do NOT study overnight! you'll need your sleep so that your mind is as clutch as possible during the exam. you can stay up overnight on saturday revising, as there aren't exams on sunday, but don't do it the night before the exam.
that said, writing notes on everything is about the best way to learn anything so you may be surprised by how much more you know now than you did when you started writing those notes.

Reply 9

The_Luvbster

Some people are visual learners though, and I know for a fact that when I start making notes I end up spending AGES and only revising a few topics :p:

Oh right! Enthalpy! It just looked different as "delta h", I guess that's why it didn't click. Do you guys revise from the revision guide (the oxford revision guide I think it's called) or from notes or units you were given in class?

Yeah, I need a 6 from either higher maths or higher chem to get into my firm university, and having gotten 5's for chem in the past two exams sessions and even worse for math... the chances of ever getting there are diminishing by the day. :smile:

Okay, goodnight everyone, and good luck with English tomorrow!

Reply 10

The_Luvbster

Sadie_F

EDIT: girl-on-ice, whatever you do, do NOT study overnight! you'll need your sleep so that your mind is as clutch as possible during the exam. you can stay up overnight on saturday revising, as there aren't exams on sunday, but don't do it the night before the exam.
that said, writing notes on everything is about the best way to learn anything so you may be surprised by how much more you know now than you did when you started writing those notes.

Easier said than done... I can never sleep the night before an exam, even if I try. The butterflies in my stomach keep me awake :frown:

Reply 11

Sadie_F

take benadryl :smile:

Reply 12

tinypony

Easier said than done... I can never sleep the night before an exam, even if I try. The butterflies in my stomach keep me awake

I went to bed early yet got no sleep at all! I kept thinking random stuff, my brain was just going off a tangent all the time...

Reply 13

W.O.N.D.E.R

IONIZATION ENERGY: is the energy needed to loose 1 mol of electons in the gaseous state ......This is the only thing i remember from definitions.
and homolgeus pair
and Enthalpy change
and i feel i wont survive chemistry (although this is the only thing i studyed :ninja:

Biology HL i still didnt revise it )
And I am gonna study all night bfr the exam....No other choice if i want to get at least my diploma,,, and i will sleep after exam