Atoms & Isotopes (AQA GCSE Physics Combined Science): Flashcards

Number of protons in an atom

Always the same

Equal to number of protons

Protons + neutrons

Same element, different neutron counts

Atomic number (proton count)

$\text{mass number} - \text{atomic number}$

Atoms losing or gaining electrons

Atoms that lost or gained electrons

Positive

Negative