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Atomic Number

Key Stage 3

Meaning

An element tile showing the Atomic Number.

The Atomic Number is the number of protons in the nucleus of an atom.

About The Atomic Number

The Atomic Number of an atom determines which element it is.
The number of protons also determines the number of electrons.

Examples

Hydrogen Helium Lithium Beryllium
Hydrogen.png
Helium.png
Lithium.png
Beryllium.png
HydrogenSymbol.png
HeliumSymbol.png
LithiumSymbol.png
BerylliumSymbol.png
Hydrogen has 1 proton so its atomic number is 1. Helium has 2 protons so its atomic number is 2. Lithium has 3 protons so its atomic number is 3. Beryllium has 4 protons so its atomic number is 4.

Key Stage 4

Meaning

An element tile showing the Atomic Number.

The Atomic Number is the number of protons in the nucleus of an atom.

About The Atomic Number

The Atomic Number of an atom determines which element it is.
Protons have a relative atomic charge of +1 so the number of protons determines the relative atomic charge of the atomic nucleus.
The number of electrons orbiting the nucleus is the same as the number of protons in the nucleus of an atom.

Examples

Hydrogen Helium Lithium Beryllium
Hydrogen.png
Helium.png
Lithium.png
Beryllium.png
HydrogenSymbol.png
HeliumSymbol.png
LithiumSymbol.png
BerylliumSymbol.png
Hydrogen has 1 proton so its atomic number is 1 and the relative atomic charge of the nucleus is +1. Helium has 2 protons so its atomic number is 2 and the relative atomic charge of the nucleus is +2. Lithium has 3 protons so its atomic number is 3 and the relative atomic charge of the nucleus is +3. Beryllium has 4 protons so its atomic number is 4 and the relative atomic charge of the nucleus is +4.

References

AQA

Atomic number (Z), page 89, GCSE Physics, Hodder, AQA
Atomic number, page 111, GCSE Combined Science Trilogy; Physics, CGP, AQA
Atomic number, page 123, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA
Atomic number, page 3-4, GCSE Chemistry, Hodder, AQA
Atomic number, page 44, GCSE Physics; The Revision Guide, CGP, AQA
Atomic number, pages 119, 339, GCSE Combined Science Trilogy 1, Hodder, AQA
Atomic numbers, page 96, GCSE Physics; Third Edition, Oxford University Press, AQA
Atomic numbers, pages 12, 13, 22, GCSE Chemistry; The Revision Guide, CGP, AQA
Atomic numbers, pages 14, 16, GCSE Chemistry; Third Edition, Oxford University Press, AQA
Atomic numbers, pages 25, 52, GCSE Chemistry, CGP, AQA
Atomic numbers, pages 25, 52, GCSE Combined Science Trilogy; Chemistry, CGP, AQA
Atomic numbers, pages 96, 97, 107, 198, 199, GCSE Combined Science; The Revision Guide, CGP, AQA
Atomic; number, pages 109, 111, 116-17, GCSE Physics; Student Book, Collins, AQA

Edexcel

Atomic (proton) number, pages 79, 174, GCSE Combined Science; The Revision Guide, CGP, Edexcel
Atomic (proton), number, page 51, GCSE Physics; The Revision Guide, CGP, Edexcel
Atomic number, page 20, GCSE Chemistry, Pearson, Edexcel
Atomic number, page 92, GCSE Physics, Pearson Edexcel
Atomic number, pages 164, 356, GCSE Combined Science, Pearson Edexcel
Atomic number; periodic table, pages 172-173, GCSE Combined Science, Pearson Edexcel
Atomic number; periodic table, pages 28-29, GCSE Chemistry, Pearson, Edexcel
Atomic numbers, page 16, GCSE Chemistry; The Revision Guide, CGP, Edexcel
Atomic numbers, pages 35, 36, GCSE Chemistry, CGP, Edexcel

OCR

Atomic (proton) number, pages 15, 16, GCSE Chemistry; The Revision Guide, CGP, OCR Gateway