Relative atomic mass
What Relative atomic mass means in Combined Science GCSE, as defined for AQA.
Definitions of Relative atomic mass
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Reference: AQA
A weighted mean of isotope masses that is not usually a whole number and is not the same as mass number.
A weighted mean of the masses of an element's isotopes, taking account of how common each isotope is.
An average mass of the atoms of an element compared with 1/12 of the mass of a carbon-12 atom.
A weighted mean of an element's isotopes' masses, so it is often not a whole number.
The weighted mean of isotope masses, so it need not be a whole number.
Topics that use Relative atomic mass
- Mass number, atomic number and isotopes (AQA GCSE)
- Relative atomic mass (AQA GCSE)
- Size and mass of atoms (AQA GCSE)
Related terms
- Atomic number
- Isotopes
- Mass number
- Nuclide notation
- Atomic structure
- Electron arrangement and outer electrons
- Empty space
- Ion formation
Using Relative atomic mass in the exam
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