Describe the composition of an atom in terms of a positively charged nucleus and negatively charged electrons

Use the terms proton (atomic) number Z, nucleon (mass) number A and isotope.

Use and interpret the term nuclide and use the nuclide notation .

Show an understanding that nuclear decay is a random and spontaneous

Show an understanding of the nature of alpha (α), beta (β) and gamma (γ) radiation.

Use equations involving nuclide notation to represent changes in the composition of the nucleus when radioactive emissions occur.

Show an understanding of background radiation.

Use the term half-life in simple calculations.

State the meaning of nuclear fission and nuclear fusion and relate these nuclear processes with the release of energy from nuclear fuels.

Discuss the applications and hazards of radioactivity.

Medical imaging – The decay of radioactive nuclei often result in the emission of gamma rays and x-rays. These rays can be used to produce an image of the internal organs of a patient. Thus allowing a doctor to diagnose the illness or problem.

Destroying cancerous cells and bacteria – The high energy of gamma rays can be used to to destroy brain tumours and kill bateria in food.

Measurement of material thickness – An increase in material thickness will decrease the intensity of (α, β, γ) radiation on the exit side of the material. By measuring the intensity at the exit side, the thickness of the material in a factory production line can be tracked continuously.

Carbon dating – radioactive carbon-14 atoms are continuously being formed naturally in the atmosphere. Plants take in these atoms by photosynthesis and are eaten by animals. When living things die, the radioactive carbon-14 no longer get replenished and the concentration will slowly decay with half life of 5700 yrs. By measureing the concentration of carbon-14, we can estimate the time duration since the death of the plant or animal.

While controlled radiation from radioactive isotopes kill cancer cells, we cannot totally avoid the damage to healthy cells.

Accidental leakage of radioactive substance can cause illness and death to living things.

Contamination of environment can disrupt the livelihood of people and animals.