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Nuclear Notation (HL IB Physics)

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Physics

Nuclear Notation

  • A nucleus can be described using straight X presubscript straight Z presuperscript straight A notation

AZX Notation, downloadable AS & A Level Physics revision notes

X presubscript Z presuperscript A notation is used to describe the constituents of a nucleus

  • The top number A represents the nucleon number or the mass number
    • Nucleon number (A) = total number of protons and neutrons in the nucleus

  • The lower number Z represents the proton or atomic number
    • Proton number (Z) = total number of protons in the nucleus

Exam Tip

In Chemistry, you may see nucleon number referred to as mass number and proton number as atomic number. Both of these are valid, just make sure you don't mistake mass number for atomic number, or vice versa.

Make sure you know that the periodic table is ordered by atomic number

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Katie M

Author: Katie M

Katie has always been passionate about the sciences, and completed a degree in Astrophysics at Sheffield University. She decided that she wanted to inspire other young people, so moved to Bristol to complete a PGCE in Secondary Science. She particularly loves creating fun and absorbing materials to help students achieve their exam potential.

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