Chemistry GCSE
Atomic number
What Atomic number means in Chemistry GCSE, as defined for AQA, OCR.
Definitions of Atomic number
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Reference: AQA
The number of protons in an atom of an element, which identifies the element and fixes its position in the periodic table.
Gives the number of protons and, in a neutral atom, the number of electrons.
The fixed number of protons that every atom of a given element has.
The number of protons in the nucleus, which identifies the element.
The number of protons in the nucleus of an atom. It determines the element.
Topics that use Atomic number
- Relative electrical charges of subatomic particles (AQA GCSE)
- The development of the model of the atom (common content with physics) (AQA GCSE)
- The periodic table (AQA GCSE)
- Topic C1: Particles (OCR GCSE)
Related terms
- Mass number
- nuclear model
- Acceptance of scientific models
- Alpha particle scattering
- Charge balance
- Development of the atomic model
- Discovery of the neutron
- Evidence and scientific explanation
Using Atomic number in the exam
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