Isotope Notation & Average Atomic Mass

Explore isotope notation for 7 elements. See mass number, atomic number, proton/neutron counts, and calculate weighted average atomic mass from natural abundances.

ISOTOPES AND ATOMIC MASS

Isotopes are atoms of the same element that differ in their number of neutrons. Atomic mass is the weighted average mass of an element's isotopes.

CORE FORMULAS

Average Mass

AP EXAM CONNECTION

Unit: Unit 1: Atomic Structure
Learning Objective: SPQ-1.B

COMMON MISCONCEPTIONS

Atomic mass is just the mass of the most common isotope.

KEY TAKEAWAYS

Atomic mass is an average based on isotope abundance.

DEEP DIVE: RELATED CONCEPTS

MASS SPECTROMETRY

Technique for measuring the mass and relative abundance of isotopes in a sample....

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