relative formula mass
What relative formula mass means in Chemistry A-Level, as defined for AQA, OCR.
Definitions of relative formula mass
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Reference: OCR
Applies to any formula unit, including ionic compounds such as NaCl, and is likewise the sum of the relative atomic masses of the atoms in the formula.
The sum of the relative atomic masses of the ions in the simplest formula unit, used for ionic compounds.
Topics that use relative formula mass
- Relative atomic mass and relative molecular mass (AQA A-Level)
- Atomic structure and isotopes (OCR A-Level)
Related terms
- Relative atomic mass
- relative molecular mass
- atomic number
- Calculation accuracy
- ionic lattices
- isotopes
- Isotopic abundance
- Isotopic abundance and its effect on the mean
Using relative formula mass in the exam
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