Physics GCSE
unchanged mass number
What unchanged mass number means in Physics GCSE, as defined for AQA.
Definition of unchanged mass number
Check what you remember
Read the wording for your board, then hide it and explain unchanged mass number in your own words. Rough notes are fine. This is a self-check, with no mark or grade.
Reference: AQA
One neutron has gone but one proton has appeared, so the total is unchanged and the mass number stays the same.
Topics that use unchanged mass number
- Nuclear equations (AQA GCSE)
Related terms
- balanced nuclear equations
- balancing equations
- beta decay
- conservation of charge
- conservation of mass number
- emitted particle numbers
- increased atomic number
- loss of energy
Using unchanged mass number in the exam
Check the command word and mark scheme for your exact question. After comparing your explanation with the reference, use the term in an answer on the linked topic. This practice does not predict an exam mark.
Practise Physics questions
Create a free account to answer exam-style questions on this topic and get feedback on your answers.
Start free
All Physics GCSE termsA week of Premium from your first lesson · Then the free plan continues · No card, no charge