Physics A-Level
Proton number
What Proton number means in Physics A-Level, as defined for AQA, OCR.
Definition of Proton number
Check what you remember
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Reference: AQA, OCR
The number of protons in a nucleus, which defines the element.
Topics that use Proton number
- Constituents of the atom (AQA A-Level)
- The nuclear atom (OCR A-Level)
Related terms
- Isotopes
- Nucleon number
- Atomic and nuclear density
- Atomic and nuclear dimensions
- Atomic structure
- Charge and neutrality
- Evidence from scattering
- Force-separation relationship
Using Proton number in the exam
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