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2.1.3 Mass number, isotopes and relative atomic mass
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Atomic number and mass number

Atomic number and mass number

The atomic number is the number of protons in the nucleus. It identifies the element because every atom of a particular element has the same number of protons.

2.1.3 Mass number, isotopes and relative atomic mass Lesson

  1. GCSE
  2. /Chemistry
  3. /2.1.3 Mass number, isotopes and relative atomic mass

Step-by-step lessons on Edexcel GCSE Chemistry 2.1.3 Mass number, isotopes and relative atomic mass. Each one builds up to exam-style questions. Nail the core quantitative topics — moles, balancing equations and calculations — early on, since they underpin higher-tier questions across every paper and topic.

Lessons