1.2

• What role do electrons play in chemical reactions?

  Electrons are involved in the changes that happen during chemical reactions.
• What are principal quantum numbers?

  Principal quantum numbers (n) indicate fixed energy levels/shells in atoms.
• How does the value of n relate to the energy level of an electron shell?

  The lower the value of n, the closer the shell is to the nucleus and the lower the energy level.
• What are atomic orbitals?

  Atomic orbitals are areas of space around the nucleus where there is a high probability of finding an electron.
• What are subshells in relation to atomic orbitals?

  Subshells group orbitals of the same type together, such as s, p, d, and f.
• What is the shape of an s orbital?

  An s orbital is spherical.
• How many electrons can an s orbital hold?

  An s orbital can hold up to two electrons.
• What is the shape of a p orbital?

  A p orbital has dumb-bell shaped lobes at right angles (px, py, pz).
• How many electrons can a p orbital hold in total?

  A p orbital can hold up to six electrons in total.
• How many different orbitals are in a d orbital?

  A d orbital has five different orbitals.
• What are the three particles that make up an atom?

  Proton, neutron, and electron
• What is the relative mass and charge of a proton?

  Relative mass 1, relative charge +1
• How many electrons can a d orbital hold in total?

  A d orbital can hold up to ten electrons in total.
• What is the relative mass and charge of a neutron?

  Relative mass 1, relative charge 0
• How many different orbitals are in an f orbital?

  An f orbital has seven different orbitals.
• What is the relative mass and charge of an electron?

  Relative mass $\frac{1}{1840}$, relative charge -1
• What does the atomic number represent?

  The number of protons in an atom
• What are isotopes?

  Atoms of the same element with different numbers of neutrons
• What is the mass number of an atom?

  The sum of protons and neutrons
• What are radioactive isotopes?

  Isotopes that are unstable and can spontaneously disintegrate
• How many electrons can an f orbital hold in total?

  An f orbital can hold up to fourteen electrons in total.
• How do electrons fill orbitals?


  Electrons fill orbitals from lower to higher energy levels.
• What is the maximum number of electrons that can occupy any orbital?


  A maximum of two electrons can occupy any orbital, each having an opposite spin.
• What happens when two or more orbitals of equal energy are available?


  Electrons will occupy them singly at first with parallel spins before filling in pairs.
• What is alpha (α) radiation?


  Positively charged helium nuclei with a mass of four units
• What is electronic configuration?


  The arrangement of electrons in an atom is called electronic configuration or electronic structure.
• What is beta (β) radiation?


  Negatively charged electrons with negligible mass
• What is the order of filling electron shells for a potassium (K) atom with 19 electrons?


  • 1s²
  • 2s²
  • 2p⁶
  • 3s²
  • 3p⁶
  • 4s¹
• What is gamma (γ) radiation?


  Very high energy electromagnetic radiation
• What is the process called when radioactive isotopes disintegrate?


  Radioactive decay
• How do α-particles behave in an electric field?


  They are attracted slightly to the negative plate
• What is the electronic configuration for a copper (Cu) atom with 29 electrons?


  • 1s²
  • 2s²
  • 2p⁶
  • 3s²
  • 3p⁶
  • 3d¹⁰
  • 4s¹
• What is the electronic configuration for a Cu²⁺ ion with 27 electrons?


  • 1s²
  • 2s²
  • 2p⁶
  • 3s²
  • 3p⁶
  • 3d⁹
• How do β-particles behave in an electric field?


  They show considerable deviation towards the positive plate
• What is ionisation?


  Ionisation is the process of removing electrons from an atom.
• How does γ-radiation behave in an electric field?


  It is unaffected by the electric field
• Why do successive ionisation energies always increase?


  Successive ionisation energies increase due to greater effective nuclear charge and decreased electron shielding.
• What happens during alpha decay?


  A helium nucleus is produced, decreasing the atomic number by two
• What happens to the shells as each electron is removed during ionisation?


  Each shell will be drawn slightly closer to the nucleus as electrons are removed.
• What happens during beta decay?


  A neutron changes into a proton, increasing the atomic number by one