Atomic Structure

Cards (63)

  • What is the charge of the nucleus?
    Positively charged
  • What particles are contained in the nucleus?
    Neutrons and protons
  • What is the charge of electrons?
    Negatively charged
  • What is the relative mass of a proton?
    1
  • What is the relative charge of a neutron?
    0
  • What is the typical radius of an atom?
    1×1010 metres1 \times 10^{-10} \text{ metres}
  • How much smaller is the nucleus compared to the atom?
    10,000 times smaller
  • Where is most of the mass of an atom concentrated?
    At the nucleus
  • How do electron arrangements change?
    With interaction with EM radiation
  • What do all atoms of the same element have in common?
    The same number of protons
  • What defines a neutral atom?
    Same number of electrons and protons
  • What are isotopes?
    Atoms with the same protons but different neutrons
  • What does the letter X represent in isotopes?
    The letter of their element
  • What does the mass number A represent?
    Number of neutrons and protons
  • What does the proton number Z represent?
    The number of protons
  • What does N represent in atomic notation?
    The charge of the atom
  • What happens if there are more electrons than protons?
    The atom has a negative charge
  • What happens if there are fewer electrons than protons?
    The atom has a positive charge
  • What occurs when electrons change orbit?
    They absorb or emit EM radiation
  • What happens when electrons move to a higher orbit?
    The atom absorbs EM radiation
  • What happens when electrons fall to a lower orbit?
    The atom emits EM radiation
  • What can happen if an electron gains enough energy?
    It can leave the atom
  • Who proposed that everything was made of tiny spheres?
    Dalton
  • What did JJ Thomson discover?
    The electron
  • What was the Plum Pudding Model?
    Electrons dispersed in positive "pudding"
  • What did Rutherford realize about the atom?
    Most of the atom is empty space
  • What did the Gold Foil Experiment demonstrate?
    Most alpha particles went straight through
  • What does deflection of alpha particles indicate?
    The nucleus must be charged
  • What does a deflection of >90° in alpha particles suggest?
    The nucleus contains most of the mass
  • What model did Bohr produce in 1913?
    The final model of the atom
  • What did Chadwick provide evidence for?
    The existence of neutrons
  • What is radioactive decay?
    A random process of nuclei changing
  • What is activity in terms of radioactive decay?
    The rate of unstable nuclei decaying
  • How is activity measured?
    In Becquerel, Bq
  • What is count-rate?
    Number of decays recorded per second
  • What is alpha decay?
    Emission of a helium nucleus
  • How ionising is alpha radiation?
    Highly ionising
  • How penetrating is alpha radiation?
    Weakly penetrating (~5cm of air)
  • What is beta minus decay?
    Emission of an electron
  • How ionising is beta radiation?
    Medium ionising