Atomic Orbitals

• What should you be able to calculate by the end of the video?

  The maximum number of electrons in a shell
• What is meant by an atomic orbital?

  A region that can hold up to two electrons
• What shapes are the s and p orbitals?

  S orbitals are spherical; P orbitals are dumbbell-shaped
• How many electrons can the first shell hold?

  Up to 2 electrons
• How many electrons can the second shell hold?

  Up to 8 electrons
• How many electrons can the third shell hold?

  Up to 18 electrons
• How many electrons can the fourth shell hold?

  Up to 32 electrons
• What happens to the energy of the shells as you move further from the nucleus?

  The energy of the shells increases
• What is the principal quantum number?

  It indicates the shell number
• What is the equation to calculate the maximum number of electrons in a shell?

  Maximum electrons = 2 times N squared
• If N equals 1, how many electrons can the first shell hold?

  2 electrons
• If N equals 2, how many electrons can the second shell hold?

  8 electrons
• If N equals 3, how many electrons can the third shell hold?

  18 electrons
• If N equals 4, how many electrons can the fourth shell hold?

  32 electrons
• What is an atomic orbital?

  A region that can hold two electrons
• What must be true about two electrons in the same orbital?

  They must have opposite spins
• What is the shape of the s orbital?

  Spherical
• How many p orbitals are there in each shell (except the first)?

  Three p orbitals
• What is the shape of the p orbitals?

  Dumbbell-shaped
• How many d orbitals are there in each shell (except the first two)?

  Five d orbitals
• What is the shape of the d orbitals?

  Complicated shapes
• How many f orbitals are there in shells four and above?

  Seven f orbitals
• What is a subshell?

  All orbitals of the same type in a shell
• What does the AQA spec refer to subshells as?

  Sub levels
• What are the types of atomic orbitals and their characteristics?

  • s orbitals: Spherical shape, one per shell
  • p orbitals: Dumbbell shape, three per shell (except first)
  • d orbitals: Complicated shapes, five per shell (except first two)
  • f orbitals: Seven per shell (from fourth shell)
• How do the maximum number of electrons in each shell relate to the principal quantum number?

  • First shell (n=1): 2 electrons
  • Second shell (n=2): 8 electrons
  • Third shell (n=3): 18 electrons
  • Fourth shell (n=4): 32 electrons
• What is the probability concept associated with atomic orbitals?

  • Atomic orbitals show a 95% probability of where an electron will exist
  • Exact location of an electron cannot be determined