How to Revise for Chemistry GCSE

Aimlessly flicking through your notes, answering question after question but not sure why, staring at a revision guide, or just sitting there feeling overwhelmed about revising? Do any (or all) of those sound familiar? Over my years as a Chemistry teacher, GCSE and A Level Chemistry examiner, A Level Chemistry author, and Chemistry tutor, I can guarantee you are not alone. In my experience, you are probably not even in the minority of students! So, close your eyes, take a deep breath in through your nose, ignore the background noises, and then let that breath out through your mouth as you open your eyes ready to focus (hint: that was your first technique that may help you mentally prepare for the task ahead!). 

Chemistry isn’t the only subject that you’re revising. In the classroom, I would stand in front of my students, using my hands to make a little block for each Chemistry topic. The block would get bigger as we added all the topics together, bigger as we added Biology and Physics and bigger still when we added English, Maths and other subjects. It would take a moment, but there was always one student who would point out that it was not possible or realistic. This means that you must have an effective revision plan. 

Plan your revision

Teachers, friends, family and the media will tell you what you should do and how you should do it. They’re just trying to help, after all. However, be aware that there is always conflicting advice. For example, some people suggest breaking the revision into small chunks, while a recent TikTok trend suggests revising until a candle goes out. One of the most important things to remember is that this is your revision and the trick is discovering what revision techniques and resources work for you!

Don’t leave your revision until the last minute because it won’t be as effective; you’re sure to feel pressured. Plus, until the exam timetables are released you can’t guarantee that you’ll only have one exam on any day. The best thing is to create your own revision timetable:

• Print a calendar off (don’t use the one on your phone, or device, as this is a distraction)

• Mark any important dates that you may have (such as friends’ or family birthdays, your team’s matches) as these can be your breaks from revision

• Then, add blocks of time for different subjects and topics (not forgetting breaks) 

Know your exam board 

Make sure you know which exam board and syllabus is yours, so you are revising the correct content. You can find our exam board-specific GCSE Chemistry content for different exam boards here:

• AQA GCSE Chemistry

• AQA GCSE Chemistry: Combined Science

• Edexcel GCSE Chemistry

• Edexcel GCSE Chemistry: Combined Science

• OCR Gateway GCSE Chemistry

• OCR Gateway GCSE Chemistry: Combined Science

• WJEC GCSE Chemistry - coming soon!

Refer to your GCSE Chemistry specification

The specification (or syllabus) is your one-stop shop for everything that can be asked in a Chemistry paper. It can contain very specific statements about things you are expected to know and be able to do. 

For example, Edexcel GCSE Chemistry:

• Investigate the preparation of pure, dry hydrated copper sulfate crystals starting from copper oxide including the use of a water bath.

While AQA GCSE Chemistry is less specific about the crystals being formed:

• Students should be able to describe how to make pure, dry samples of named soluble salts from information provided.

As an examiner, I have always commented in reports about how students’ descriptions of making crystals of a soluble salt are often poor, despite it being a common exam question with a common answer. The basic answer is: mix, filter, heat until crystals start to form, leave to dry.

The specification can also contain more general statements. For example, all GCSE Chemistry exam boards expect you to be able to write word equations and balanced chemical equations but, potentially, for any chemical reaction.

From years of marking exams, I have found that other key concepts that students find challenging in exams include:

• Chemical bonding (ionic, covalent, metallic) - this always comes up in exams and frequently shows that students have the different types of bonding mixed up

• Chemical analysis - again, this is always asked in exams but causes problems because of the sheer number of chemical tests. This topic is ideal for flashcards!

• Balancing chemical equations - this seems to be a do- or don’t-get-it aspect of chemistry, but being able to balance equations can unlock the calculations 

• Calculations (quantitative chemistry) - you don’t have to be good at GCSE Maths to be good at the calculations in Chemistry because they all have a set pattern to getting them right

• Ionic equations and electrochemistry - this has been commented on in every GCSE Chemistry exam that I have marked

• Chemical equilibria - this is usually on higher-tier papers and it is the specific nature and wording of answers that cause the main issue 

The specification can also be a useful guide to your GCSE Chemistry revision. If you get a list of the topics, you can RAG rate them. This means that you colour the topics red if you don’t understand  them, amber for topics that you think you understand but need to practise or work on, and green for the topics that you are most confident with. This helps you identify which topics you should spend more time on (red) and which topics you should spend less time on (green).

Use revision notes

Remember that our revision notes at Save My Exams are written specifically for each exam board and specification. The navigation panel at the side ticks areas that you’ve covered, but you can untick any that you want to revisit!

Two of the most common mistakes that I have seen many students make with revision notes are:

Copying them out and colour-coding different sections
At the end of it, students have a pretty page that often contains the exact same information as the page they used to make their notes. 

Just “reading” revision notes
If you know it, then reading about it is wasting your revision time. If you don’t know it, then simply reading about it may not help because you need some practice.

Several studies have shown that re-reading, highlighting or summarising revision notes are the most ineffective revision techniques. This is because they are all passive techniques and do not help you consolidate your learning.

I often had my students create RAG-rated lists. One for topics simply based on the title, one for topics after going through notes, and one for topics after practising questions. Any topic that featured in all three was definitely a topic to revise!

Create flashcards

Flashcards can be amazing in GCSE Chemistry but they are not suitable for all topics, especially given the time it can take to make them. With a question or statement on one side and the answer on the other, they can make topics with a lot of fact recall more manageable.

One area in Chemistry that would be ideal for flashcards is chemical analysis. You can put a description of the chemical test on one side and the result on the other. 

I have seen students improve greatly using flashcards forwards AND backwards. Traditionally, you use flashcards forwards by reading the question, checking your answer and giving yourself a pat on the back if you got it correct. 

You can also use them backwards by reading the answer and working out what the question could be. This is a higher level of thinking, which can challenge you and really help you remember the topic. You can also add little notes to your flashcards as you work through past papers. For example, you might see that a mark scheme will not accept red for the colour of bromine, so you could add this to the relevant flashcard. 

Learn essential formulas and equations

The specifications often say that knowing the formulas of common substances mentioned in the syllabus is a great idea. Here are several chemical formulas that it can be helpful to know:

• Carbon dioxide - CO₂

• Water - H₂O

• Hydrogen - H₂

• Oxygen - O₂

• Methane - CH₄

• Ammonia - NH₃

• Hydrochloric acid - HCl

• Sulfuric acid - H₂SO₄

• Sodium hydroxide - NaOH

There are some equations that you should be able to recall, rearrange and use:

• Moles = mass ÷ relative atomic or molecular mass

• Concentration = mass ÷ volume

• Concentration = moles ÷ volume (Higher Tier content)

• Percentage yield = actual yield ÷ theoretical yield x 100

• Volume = moles x molar volume

Get familiar with the periodic table 

Our revision notes give the relevant information about the periodic table:

• AQA GCSE Chemistry Periodic Table

• Edexcel GCSE Chemistry Periodic Table

• OCR Gateway GCSE Chemistry Periodic Table

• WJEC GCSE Chemistry Periodic Table - coming soon!

One of the things I would do to get my students more familiar with the periodic table was to play “signposts”. For example, I would ask: 

• What is the relative atomic mass of the element that is 2 down and 4 across? 

  • The answer is 12 because carbon is 2 down and 4 across, has an atomic number of 6 and a relative atomic mass of 12

My students would very quickly learn the masses of some common elements, which can help with calculations because you don’t need to look values up.

We would then progress to electronic configurations with simple questions to build confidence, such as:

• How many electron shells does carbon have?

  • Carbon has two electron shells because it is 2 down

• How many outer electrons does carbon have? 

  • Carbon has four outer electrons because it is 4 across

• How many elements are in the first, second and third periods (rows) of the periodic table?

  • The first period contains two elements

  • The second period contains eight elements

  • The third period contains eight elements

  • This links to electrons in shells as the first shell can hold a maximum of two electrons; the second shell can hold a maximum of eight electrons, etc.

These signposts gave my students confidence in their abilities to draw the electronic configuration for any of the first 20 elements, up to calcium.

You should also be aware of the opposites within the periodic table:

• Metals are on the left and non-metals are on the right

• As you move down Group 1 (on the left) reactivity increases, while as you move down Group 7 (on the right) reactivity decreases

Practise GCSE Chemistry past papers

This is something that you will do in your lessons and may do, for yourself, at home. What do you actually do when you do practice papers? You probably work through a practice paper, have it marked against the mark scheme (by you or your teacher) and, maybe, make corrections.

When we completed a practice paper, I would get my students to make a list of the things they got wrong. After two or three past papers, I would ask my students if there were any topics that they were consistently getting wrong. Comparing these mistake lists meant that my students could easily identify different areas that they should work on.

Another technique my students found very useful was using mark schemes. We didn’t use them in the traditional sense of just marking a practice paper. I would get them to look through a mark scheme, without seeing the practice paper. The challenge was to work out what the question was from the answer. This was helpful because they could see what examiners were specifically looking for, as well as identify topics that they were more or less confident with.

So, there would be answers where:

• They couldn’t deduce the question at all, e.g. a numerical answer like “42”

• They could easily determine the question, which meant that they were probably more capable with that topic

• They couldn’t get close to the actual question, which meant they had just found a topic that they needed to focus their revision on

These past paper tasks aim to identify areas for focused revision. This means that instead of revising things you already know, which we are all guilty of, you revise the areas that are your weaknesses and can potentially lead to big gains in terms of exam marks.

FAQs

How many topics are there in GCSE Chemistry?

This depends on your exam board.

• AQA GCSE Chemistry = 10 topics

  • Paper 1 tests topics 1-5 

  • Paper 2 tests topics 6-10

• Edexcel GCSE Chemistry = 9 topics

  • Paper 1 tests topics 1-5 

  • Paper 2 tests topic 1 and topics 6-9

• OCR Gateway GCSE Chemistry = 6 teaching topics (C1-C6) and the practical activity skills topic (C7)

  • Paper 1 (Foundation) and Paper 3 (Higher) test topics C1-3 and C7

  • Paper 2 (Foundation) and Paper 4 (Higher) test topics C4-6 and C7 

  • Papers 2 and 4 also assume knowledge from topics C1-3

• WJEC GCSE Chemistry = 12 topics

  • Paper 1 tests topics 1.1-1.6

  • Paper 2 tests topics 2.1-2.6

  • Paper 3 is a practical assessment carried out in your exam centre

How to revise Chemistry GCSE in one day?

• The simple answer is don’t! It’s unrealistic to think that you can effectively revise at least two years worth of content in one day!

• If you really must, then use the specification, past papers and mark scheme to identify your weakest areas and focus your revision on those topics.

• Work in chunks to break your revision up and try to keep one chunk to one topic.

How long does it take to revise Chemistry GCSE?

There is no answer to this question because it depends on so many things:

• How much you already know

• How many practice papers you have worked on

• How well you can answer exam questions

• If you’ve already dedicated some time to revision throughout your lessons

At the latest, I would recommend starting your revision when your school starts revising with you. There are two trains of thought: 1) earlier revision equals more revision and, therefore, better marks, or 2) earlier revision means that you will forget more of the topics that you revised first. So, keep your revision to small, manageable chunks and repeat topics to reinforce them.