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Measurement of Relative atomic mass

Answer Text:
Measurement of Relative atomic mass
- RAM of elements is determined by an instrument called Mass Spectrometer.
- The instrument can also be used to determine the relative abundance of isotopes.
- The use of a mass spectrometer in determining the RAM of elements is called mass spectrometry.
Note:
- Generally the relative atomic mass of an element is closest in value to the mass of the most abundant isotope of the element.
Example: Diagram of a spectrometer trace for Lithium

Explanations:
- The trace has two peaks indicating that there are two isotopes for lithium.
- The first peak occurs at a relative isotopic mass of 6
and the second at 7; these are the RAM of the two
isotopes respectively.
- The percentage abundance of the isotope with RAM of 6 (#\ ^6Li#) is 9 while the RAM of the isotope with
RAM 7 (#\ ^7Li#) is 91.