## A-level Chemistry what to revise in summer between year 12 and 13.

When you start A-level Chemistry it can be a bit of a shock to the system – you quickly realise that it’s nothing like GCSE! Unfortunately though, it can take a while for it to all start to fall into place, and when it does it can feel like you’ve missed quite a lot.

This means that it’s a good idea to use the summer between year 12 and 13 to go back to basics and revise the stuff that might not have gone in first time round, but will become really important in the second year of A-level Chemistry.

You don’t want to spend all your summer studying though Year 2 will be hard work so you need to make plenty of time to have a rest and a life.

Here’s what I recommend you focus on to make good use of your time and get year 2 off to a strong start:

## 1.Balancing equations

If you get that feeling in the pit of your stomach whenever you have to balance an equation, you need to do some practice. You’ll have to balance equations in every topic for Chemistry and a few basic worksheets may be all you need to build up your confidence to the point where you don’t need to panic anymore.

## 2. Redox and ionic equations

You’ll need to be confident with these for year 2 as they show up quite a bit, so learn the rules for working out oxidation numbers and putting the equations together. Make sure you also know how to write ionic equations for reactions that are not redox reactions (e.g. acid-base reactions).

## 3. Amount of substance calculations

At this point, you’re probably pretty confident with basic moles calculations by now, but can you do the more advanced calculations, such as back titrations, percentage purity etc.? If not, this is something to work on over the summer.

## 4. Basic organic nomenclature and mechanisms

You’ll have a whole new set of organic reactions to learn in year 2, but the basics of nomenclature and how the mechanisms work are still the same. If you’ve been relying on rote learning the mechanisms up until now, it’s worth taking your time to look back at the mechanisms and make sure you actually understand them – why do they arrows point a certain way, and why does each compound undergo a particular mechanisms. Understanding the mechanisms will make learning the new ones a lot easier. The year 2 organic questions also mix the year 1 and 2 reactions together, so you need to fill in the gaps in your knowledge now before they start to cause problems.

## 5. Algebra

If you haven’t come across a calculation question that requires you to simplify an equation to get x yet, it’s only a matter of time. If you’re not doing A-level maths, you’re likely to be a bit rusty with this, so revise it now so you’re all ready for when you have a topic test that includes an 8 mark equilibrium algebra question in the 3rd week of September. To get you started, I have a 4 part video lesson here, which will teach you how to calculate the abundances of isotopes using algebra (mass spectrometry topic). This lesson also recaps on the basics of algebra.

## 6. Hess’s cycles

You learned how to calculate enthalpy changes for covalent compounds using Hess’s cycles in year 1. In year 2, you’ll use the same rules to construct Born-Haber cycles to calculate the enthalpy changes for ionic compounds, and this is likely to come quite early in year 2. If you didn’t quite get it first time round you’ll struggle, so take another look over the summer and the year 2 version will be much easier.

## FOR AQA STUDENTS: Time of flight mass spectrometry calculations

These appear right at the start of the year 1 specification, so it’s likely this was either taught in the first few weeks and went completely over your head, or your school decided to skip all but the most basic calculations. These questions aren’t actually that bad, but if you’ve never really tried them, now’s the time – they’ve come up a lot on the new specification papers, so you can pretty much guarantee they’ll come up on one of your mocks or topic tests pretty soon.