In short: Active recall means closing the book and getting information out of your head and onto the page. Reading and copying out notes is learning. Revision is retrieving what you learned, and every time you fetch something from memory it gets easier to find next time.
Revision is not about how much you can fit in your head. It is what you can pull out of it and put on the page, because that is what the exam asks you to do. Reading notes and copying them out feels productive, but it is not the same thing.
What active recall means
Active recall, also called retrieval practice, is any way of testing yourself on something you have already learned. You try to produce the answer first, and only then check it. The effort of fetching the information is what strengthens it.
Re-reading is different. The page is in front of you, so everything looks familiar, and familiar feels like known. The exam will not give you the page.
Two things to retrieve: knowledge and skills
In A Level Chemistry you need to retrieve two kinds of thing.
- Knowledge: definitions, equations, conditions, colours, mechanisms and trends.
- Skills: using that knowledge to solve the problem in front of you, such as a moles calculation.
A definition. Cover your notes and write out the definition of first ionisation energy: the energy required to remove one electron from each atom in one mole of gaseous atoms to form one mole of gaseous 1+ ions. Then write the equation with state symbols:
X(g) → X⁺(g) + e⁻
Now check it. Did you include "gaseous", "one mole" and "1+"? Those small words are usually where the marks are lost.
A calculation. Don't re-read a worked example about moles. Close it and try a fresh question. Start with the amount in moles using n = m ÷ M or n = c × V (with V in dm³), then use the balanced equation to link the reacting amounts. If you get stuck halfway, that is useful: it shows you exactly which step needs more work.
Three ways to do it
- Blank page. Write down everything you can remember about a topic, such as bonding or halogenoalkanes, with no notes. Then compare with your notes in a different colour and fill the gaps.
- Flashcards. Question on the front, answer on the back. Say or write the answer before you turn the card over. Put the cards you got wrong back in the pile, and keep going.
- Past paper questions. Do them closed book and under exam conditions where you can. Then mark them honestly using the mark scheme, and write down what you missed.
Rich's tip: Close the book and test yourself. Flashcards, a blank page or past paper questions.
Spacing it out
One burst of recall the night before is better than nothing, but fetching something again after a gap is where it really sticks. A simple pattern that works for many students:
- Test yourself on a topic soon after you learn it, the same week.
- Come back to it a few days later.
- Come back again after a week or two.
Mix topics too. A page of only moles questions teaches you the method. A mixed set makes you work out which method to use, which is what the exam does.
Common mistakes
- Spending most of your time on notes, and almost none on testing yourself.
- Checking the answer too soon, before you have really tried.
- Only testing yourself on the topics you like.
- Marking generously. If the mark scheme wants "gaseous" and you did not write it, you did not get the mark.
For how to build revision into your week in Year 12, see Study habits for Year 12 Chemistry.
If you want something to test yourself with, Dexter, the A Level Chemistry tutor I built, can write quick questions on the topics in your course and show you a mark scheme to check against.