Nuclear physics

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Sample objectives

What this unit covers

• The atom: Explain the composition of an atom, highlighting the presence of a positively charged nucleus and negatively charged electrons that orbit around it.
• The atom: Understand that atoms can become positive ions by losing electrons or negative ions by gaining electrons.
• The nucleus: Explain what the nucleus is made of, specifically mentioning protons and neutrons.
• The nucleus: Identify the relative charges of protons, neutrons, and electrons, which are +1, 0, and -1, respectively.
• Detection of radioactivity: Understand the concept of background radiation.
• Detection of radioactivity: Identify the main sources contributing to background radiation, which include: (a) radon gas in the atmosphere, (b) rocks and buildings, (c) food and beverages, and (d) cosmic rays.
• The three types of nuclear emission: Explain that radiation is emitted from a nucleus in a spontaneous manner and that its direction is random.
• The three types of nuclear emission: Identify alpha (α), beta (β), and gamma (γ) emissions from the nucleus by recalling their characteristics, including their nature, relative ionising effects, and penetrating abilities.
• Radioactive decay: Understand that radioactive decay involves a transformation in an unstable nucleus, which may lead to the release of alpha (α), beta (β), or gamma (γ) radiation. Recognize that these transformations occur spontaneously and randomly.
• Radioactive decay: Recognize that during alpha (α) or beta (β) decay, the nucleus transforms into that of a different element.
• Half-life: Define the half-life of a specific isotope as the duration required for half of the nuclei in a sample of that isotope to decay; recall and apply this definition in straightforward calculations, which may involve data from tables or decay graphs (calculations will exclude background radiation).
• Half-life: Determine the half-life using data or decay graphs that do not account for background radiation.
• Safety precautions: Identify the impacts of ionising nuclear radiation on living organisms, which include cell death, genetic mutations, and the risk of cancer.
• Safety precautions: Explain the safe methods for transporting, utilizing, and storing radioactive materials.