atomic number
What atomic number means in Chemistry A-Level, as defined for AQA, OCR.
Definitions of atomic number
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Reference: AQA
The number of protons in the nucleus, and it alone fixes which element you have.
Gives the proton count, which fixes the element.
Topics that use atomic number
- Mass number and isotopes (AQA A-Level)
- Atomic structure and isotopes (OCR A-Level)
Related terms
- isotopes
- mass number
- relative isotopic mass
- abundance ratios
- acceleration to constant kinetic energy
- base peak
- Calculation accuracy
- carbon-13 satellite
Using atomic number in the exam
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