counting neutrons
What counting neutrons means in Physics GCSE, as defined for AQA.
Definitions of counting neutrons
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Reference: AQA
The upper number, the mass number, gives protons plus neutrons, so the neutron count is found by subtracting the atomic number.
Working out the number of neutrons by subtracting the atomic number from the mass number.
Topics that use counting neutrons
- Mass number, atomic number and isotopes (AQA GCSE)
Related terms
- atomic number
- identity, charge and mass
- ions
- isotopes
- mass number
- neutral atoms
- nuclide notation
- nuclide symbols
Using counting neutrons in the exam
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