Radiation

• Radioactive decay


  Process which radioisotopes decay to form a stable nucleus by giving out radiation
• Alpha particle

  • Charge: +2
  • Stopped by piece of paper
  • Represented by: $^4_2He$
• Beta particle

  • Charge: -1
  • Stopped by thin sheet of aluminium
  • Represented by: $^0_{−1}He$
• Gamma rays

  • Charge: 0
  • Stopped by thick layers of lead, or concrete
• Neutron

  $^1_0n$
• Proton

  $^1_1p$
• Alpha decay

  • Mass number drops by 4
  • Atomic number drops by 2


  Example:

  $_{\,\,84}^{210}Po \to _{\,\,82}^{206}Pb +$$_2^4He$
• Beta decay

  • Mass number unchanged
  • Atomic number increases by 1 


  Example:

  $_{\,\,82}^{209}Th \to _{\,\,83}^{209}Ra +$$_{-1}^0e$