Chemistry GCSE
Isotopes
What Isotopes means in Chemistry GCSE, as defined for AQA.
Definitions of Isotopes
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Reference: AQA
Atoms of the same element with different numbers of neutrons and therefore different mass numbers.
Atoms of the same element with the same number of protons but different numbers of neutrons.
Atoms of an element that differ only in neutron number, not in proton number.
Topics that use Isotopes
- Development of the periodic table (AQA GCSE)
- Relative atomic mass (AQA GCSE)
- Relative electrical charges of subatomic particles (AQA GCSE)
Related terms
- Relative atomic mass
- Atomic number
- Charge balance
- Conflict between ordering principle and chemical properties
- Development of the periodic table
- Discovery of new elements
- Evidence-based acceptance of models
- Incompleteness of scientific evidence
Using Isotopes in the exam
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