Radioactive decay

• In what unit is activity of radioactive decay measured?

  Becquerels (Bq)
• What is beta radiation?

  • A high-speed electron
  • Ejected from the nucleus
  • Occurs when a neutron changes into a proton
• What are the properties of alpha radiation?

  • Low penetration
  • Travels a few centimeters in air
  • High ionizing power
• What are the properties of beta radiation?

  • Medium penetration
  • Travels several meters in air
  • Moderate ionizing power
• What are the properties of gamma radiation?

  • Very high penetration
  • Travels far in air
  • Low ionizing power
• How many protons and neutrons make up an alpha particle?

  Two protons and two neutrons
• What is beta radiation composed of?

  A high-speed electron
• What type of radiation is characterized by high penetration and low ionizing power?

  Gamma radiation
• What are the effects of alpha decay on the nucleus?

  • Nucleus loses two protons and two neutrons
  • Both the mass and charge decrease
• What are the effects of beta decay on the nucleus?

  • A neutron turns into a proton and an electron
  • An electron is ejected from the nucleus
  • Charge decreases
  • Mass remains the same
• What are the effects of gamma decay on the nucleus?

  • The nucleus releases energy
  • There is no change in mass or charge
• What are the uses of different types of radiation?

  Alpha radiation:

  • Smoke detectors

  
  

  Beta radiation:

  • Industrial thickness testing

  
  

  Gamma radiation:

  • Medical treatments
• What happens to mass and charge during alpha decay?

  Both mass and charge decrease
• How does beta decay affect the nucleus's charge and mass?

  Charge increases, mass stays the same
• During gamma decay, how does the nucleus change?

  It releases energy without changing the nucleus's mass or charge
• What is radioactive contamination?

  • Radioactive materials get on or into something
  • Danger arises from radiation emitted during decay of contaminating atoms
• What is irradiation?

  • An object is exposed to radiation
  • Object doesn't become radioactive
  • Only receives radiation energy
• What characterizes renewable energy?

  It can be replenished
• What is biofuel?

  Biofuel is made from plants and animal waste
• What are different types of renewable energy?

  • Wind energy from moving air
  • Hydroelectricity from flowing water
  • Geothermal energy from inside the earth
  • Tidal energy from rising/falling sea levels
  • Solar energy from sunlight
  • Wave energy from ocean waves
• What is geothermal energy?

  Heat from inside the earth
• What is tidal energy?

  Energy from rising and falling sea levels
• Compare renewable and non-renewable energy sources.

  Renewable:

  • Solar, wind, biofuel
  • Minimal pollution
  • Impacts (e.g., wind turbines)
  • Depend on cost
  • Reduces environmental damage

  
  

  Non-renewable:

  • Coal, fossil fuels, nuclear
  • Pollution
  • Used for transport, electricity, and heating