Nuclear Equations (CIE A Level Physics)

• Nuclear reactions can be represented by balanced equations of nuclei in the AZX form

AZX notation for atomic nuclei

• 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

Step 1:            Balance the nucleon numbers (the top number)

235 + 1 = 95 + 139 + x(1) + 7(0)

Step 2:            Rearrange to find the value of x

x = 235 + 1 − 95 − 139 = 2