atomic structure

• How is the plum pudding model described?

  As a pool of positive charge with negative particles
• What particles were unknown during the plum pudding model's time?

  Electrons, protons, and neutrons
• What is the current model of the atom centered around?

  A nucleus at the center
• What particles make up the nucleus?

  Neutrons and protons
• What is the relative mass of neutrons and protons?

  Each has a relative mass of one
• What is the significance of energy levels in the atom?

  Electrons orbit the nucleus at different energy levels
• Who conducted the alpha scattering experiment?

  Ernest Rutherford
• What was the purpose of Rutherford's alpha scattering experiment?

  To investigate the structure of the atom
• What was the key finding from Rutherford's experiment regarding alpha particles?

  Most particles traveled straight through the foil
• What conclusion was drawn about the atom from the experiment?

  The atom is mostly empty space
• Why must the mass in the center of the atom be positive?

  Due to the repulsion of alpha particles
• What is an isotope?

  An atom with the same protons but different neutrons
• How does the mass number change when a neutron is added to carbon-12?

  It becomes carbon-13
• What happens to the charge of an atom when neutrons are added or removed?

  The charge does not change
• What defines an ion?

  An atom with the same protons but different electrons
• Why is the proton number important for an element?

  It is like the fingerprint of the element
• What are the three types of radiation mentioned?

  Alpha, beta, and gamma
• What is alpha radiation?

  Emission of alpha particles from the nucleus
• How does alpha radiation affect materials?

  It is strongly ionizing but travels short distances
• What is a common use of alpha radiation?

  Used in smoke detectors
• What is beta radiation?

  Emission of fast-moving electrons from the nucleus
• How does beta radiation differ from alpha radiation in terms of ionization?

  Beta is moderately ionizing
• What is a typical use of beta radiation?

  Material thickness testing
• What is gamma radiation?

  Emission of electromagnetic waves from the nucleus
• How does gamma radiation differ in terms of ionization?

  It is weakly ionizing
• What is a common use of gamma radiation?

  Sterilizing medical equipment
• What is half-life in the context of radiation?

  The time taken for radioactive nuclei to halve
• What causes a nucleus to become unstable?

  Gaining too many neutrons
• How is radiation measured?

  With a Geiger-Muller counter
• What is the nature of radioactive decay?

  It is a random process
• What does activity refer to in radiation?

  The rate at which the source decays
• How does the activity of a radioactive source change over time?

  It decreases as time passes
• What are the two types of radiation risks mentioned?

  Irradiation and contamination
• What is irradiation?

  Exposure to radiation
• How can irradiation be reduced?

  By using lead-lined boxes
• What is contamination in the context of radiation?

  Radioactive particles getting onto objects
• How can contamination be prevented?

  By wearing correct PPE
• Why is alpha radiation a significant risk for contamination?

  It causes damage in a localized area
• What are the key differences between alpha, beta, and gamma radiation?

  • Alpha: Strongly ionizing, travels few cm, stopped by paper
  • Beta: Moderately ionizing, travels few meters, stopped by aluminum
  • Gamma: Weakly ionizing, travels kilometers, stopped by lead
• What are the implications of half-life in radioactive decay?

  • Time taken for radioactive nuclei to halve
  • Varies widely among different substances
  • Important for understanding radiation safety