1.2.A—Explain the quantitative relationship between the mass spectrum of an element and the masses of the element’s…

Explain the quantitative relationship between the mass spectrum of an element and the masses of the element’s isotopes.

• The mass spectrum of a sample containing a single element can be used to determine the identity of the isotopes of that element and the relative abundance of each isotope in nature.
• The average atomic mass of an element can be estimated from the weighted average of the isotopic masses using the mass of each isotope and its relative abundance.
  • Exclusion: Interpreting mass spectra of samples containing multiple elements or peaks arising from species other than singly charged monatomic ions will not be assessed on the AP Exam.