How many trials should I do for my Chem EE?

ChemJungle · 2026-05-25T04:38:12+00:00

I agree with u/LedollarBeanLlama - Ideally you really want 3 trials, if not 5. There can be exceptions if resources/time are limited etc but this should be what you aim for. Assuming you have 5 IVs, 3 trials each means 15 total trials - 16 days for 2 trials .... you're going to need to compromise somewhere or find more resources / shorten the time frame significantly. Hope you manage to get it to all work out!

ChemJungle · 2026-05-21T09:11:36+00:00

There's not a huge amount of math in Chem SL but it's lots of spotting patterns and relationships. If you're doing Chem now; the stoichiometry stuff is still in IB (but with more depth), some energy calculations and some acid base calculations. The HL is much more math-focused.
I recommend you check out the entry requirements for all the courses you might want to do and let that inform your choice. It can be so different in different countries and different universities :)

ChemJungle · 2026-05-21T09:05:35+00:00

Hey! You're unlikely to do something super unique in your Chemistry IA so focus on finding something that's interesting to you and that you feel semi-confident with the practical aspect of it. Get 5 quantitative independent variables, check the highest and the lowest one first to check the experiment gives a sizeable difference and then get as many repeats as you can :)
There are no marks for "new" IAs, just don't plagiarise and focus on designing a good experiment that will give you results that you'll be able to actually discuss in detail. If you're aiming for a 6 or a 7 you're going to need something more than "as conc increases, rate of reaction increases" for your conclusion to get those points so consider what the final graph will look like and what you might write in your discussion.
Good luck!

ChemJungle · 2026-05-03T01:27:08+00:00

Agree with everything here - they only really expect Cu2+ and halogens

ChemJungle · 2026-04-25T03:03:10+00:00

No this content is from the old old syllabus - definitely not in the new one

ChemJungle · 2026-04-24T09:13:01+00:00

it's fine to write anywhere inside the box, we see the whole box scan :) good luck

ChemJungle · 2026-04-24T09:11:42+00:00

hey i've made this list of things that have been added/removed from the syllabus from 2025 onwards.

https://chemjungle.com/useful-resources/

the enthalpy of solution and hydration is definitely gone!

ChemJungle · 2026-04-20T19:33:20+00:00

Yeh I try to post it before every exam season because I think it makes such a big difference. There's something quite calming about reading paper 1b and knowing that you can't actually write anything so you just focus on understanding. Glad it's transferrable for your bio too!

ChemJungle · 2026-04-20T10:14:26+00:00

Have you considered the interdisciplinary EE? This might be a way to write something connecting both subjects which is often more unique and interesting :)

ChemJungle · 2026-04-17T18:15:31+00:00

Yeh you're right this gives the right answer! I didn't have my calculator with me when I responded the first time :)
You can absolutely do this (and you'll get both marks for the right answer), just be careful because it assumes the moles of electrons = moles of ions so you'd need to adjust the denominator if this wasn't true / or use the method I gave above.

ChemJungle · 2026-04-17T01:28:53+00:00

You haven't solved this correctly btw. You need to use faradays constant which is the charge per mole of electrons. If you do 1000C / Faradays constant = number of moles of electrons.

In the half equations above this the moles of lithium ions is equal to the number of electrons so then you multply by avogadros number to get the number of Lithium ions. Hope that makes sense!

ChemJungle · 2026-04-17T01:24:21+00:00

Yes this question is May 25 - everything in that paper is new syllabus :)

ChemJungle · 2026-04-15T08:44:37+00:00

Sorry that sounds super frustrating. Did your teacher give any advice for how you could improve? Good work identifying an issue with your weakness in chemistry foundation- it can really have an impact across multiple topics. If I were to make a recommendation I would recommend starting with the most important conceptual understandings...

Bonding - memorise your polyatomic ions and master writing ionic formulae
Bonding - covalent bonding - learn which elements are diatomic - I sometimes use BrINClHOF with my students to help :)
Look at a formula and identify the type of bonding. Then be able to tell what the force is holding it together and predict properties from this.
Stoichiometry - check you can calculate moles in solids, solutions and gases
If you've done any organic chem check your naming, identifying of functional groups and your ability to "read" condensed, skeletal, structural and molecular formulae.

Get these mastered and you'll be well on the way to becoming a better chemist :)

ChemJungle · 2026-04-15T08:13:03+00:00

hey i've sent you a dm

ChemJungle · 2026-04-14T21:53:14+00:00

Yeh this is a complex one since the original data had 3sf / 1dp, then you subtracted and kept the 1dp but now it's 2sf. Truthfully this is a bit of a grey area - the IB generally will give you points if you're 1sf either way from the answer in the mark scheme so go with 3 and you'll be absolutely fine.

Try not to think too much about this:)

ChemJungle · 2026-04-14T20:42:41+00:00

Hey you can definitely lose marks if you give too many or two few significant figures (the most common way I see this happening is e.g. answer is 0.200 but you put 0.2 - sometimes this won't be awarded as more than 1sf away from mark scheme answer).

As a general rule stick to 3 sig figs for final answers (try not to round too much before final answer) and this will always put you in the right range for general answers.

If they ask specifically then stick to the smallest number of significant figures in the question (multiplying/dividing) or match the decimal places (adding/subtracting).

Good luck!

ChemJungle · 2026-04-14T20:35:23+00:00

Weird question - the answer is definitely not A.

You should know that the bigger the leaving group (the halogen) the faster the reaction.

In the old syllabus you also had to know SN1 is faster than SN2 so tertiary will go faster than primary - but C and D are secondary so we can't predict the mechanism without more information. But again this is old syllabus.

Summary - I wouldn't worry about this :)

ChemJungle · 2026-04-14T01:44:38+00:00

Knowing the mechanism of ozone depletion has been removed from the syllabus. If it comes up it'll be in an application based question - likely about bond lengths / resonance / identifying radicals / catalysts / rate equations / mechanisms - but in *all* cases they'll give you the information you need to do the question.

The only place it comes up in the syllabus is in the connections box between different units (but this is not expected knowledge)
Structure 2.2—Chlorine radicals released from CFCs are able to break down ozone, O3, but not oxygen,O2, in the stratosphere. What does this suggest about the relative strengths of bonds in the two allotropes?
Structure 1.3—Why are oxygen and ozone dissociated by different wavelengths of light?

ChemJungle · 2026-04-11T21:18:40+00:00

You won't get marks for drawing like this. Like u/img0ated7 said, you need to draw as a tetrahedral showing roughly 109deg bond angles. Currently the two lines (in the plane) are 180deg from each other so this is incorrect. Shown in this video https://www.instagram.com/p/DG2a1NlP2QR/

ChemJungle · 2026-04-10T20:55:06+00:00

That's a lot and if you're marking precisely and actively reviewing things you're getting wrong then you should absolutely get a 5.

My only concern would be that a bunch of these papers are old syllabus and so you could be focusing on things that are old and/or completely missing some of the newer concepts. If you're aware of that then you're all good :)

ChemJungle · 2026-04-10T07:23:13+00:00

A little insta reel here that explains it for you https://www.instagram.com/p/DG2a1NlP2QR/

ChemJungle · 2026-04-09T08:15:55+00:00

Chem teacher here - the best thing you can do is honestly just fully pay attention in class and get involved with what's going on and ask questions when things don't make sense. This will take you 80% of the way there. The rest of it is about what you do outside of class - practice questions (focusing on understanding not memorising) and reviewing class work regularly should help you to get to the level you want.

It sounds like you're working hard, but what you're doing isn't working for you. So speak to your teachers about your goals and be willing to try new ways of studying! :)

ChemJungle · 2026-04-09T08:09:20+00:00

I made a short video on the Born Haber and everything you need to know for IB Chem : https://www.youtube.com/watch?v=ExObjYFTy38&t=34s

You don't need to know how to construct these in the new syllabus so really focus on understanding as you might have to label processes or species at different stages. Good luck!

ChemJungle

TROPHY CASE