Physics A-Level
Isotopes
What Isotopes means in Physics A-Level, as defined for AQA, OCR.
Definitions of Isotopes
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Reference: AQA
Atoms of the same element with the same proton number Z but different nucleon numbers A, so they have different numbers of neutrons.
Nuclei of the same element with the same proton number but different nucleon number, hence different neutron numbers.
Atoms with the same proton number but different numbers of neutrons.
Topics that use Isotopes
- Constituents of the atom (AQA A-Level)
- The nuclear atom (OCR A-Level)
Related terms
- Nucleon number
- Proton number
- Atomic and nuclear density
- Atomic and nuclear dimensions
- Atomic structure
- Charge and neutrality
- Evidence from scattering
- Force-separation relationship
Using Isotopes in the exam
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