Electronic Structure

Cards (26)

  • According to Democritus, the world is made up of tiny indivisible particles called atomos.
  • In 1803, John Dalton proposed the solid sphere of an atom.
  • In 1897, Joseph John Thomson (JJ Thomson) discovered the electron and made the plum pudding model.
  • In 1911, Ernest Rutherford discovered the nucles and proposed the nuclear model.
  • In 1913, Niels Bohr discovered orbits.
  • Orbits are also known as energy levels (n).
  • Ground state is the original orbit of the electron
  • Excited state is the highest atomic orbit.
  • In 1924, Louis de Broglie made the quantum mechanical model and developed the wave-particle duality.
  • S < 2
    P < 6
    D < 10
    F < 14
  • Principal Quantum Number (n)
    • Refers to the distance of the electrons from the nucleus
    • Known as the shell
    • Computed by 2n^2.
  • Azimuthal Quantum Number (l)
    • Refers to the shape of the atomic orbit.
    • Computed by n - 1.
  • Magnetic Quantum Number (ml)
    • The number of orbitals in a subshell.
    • The values are from -l to +l.
  • Electron Spin Quantum Number (ms)
    • Indicates the spin of the electron.
    • -1/2 (counterclockwise) or +1/2 only (clockwise).
  • Electron Configuration - shows how the electrons are distributed in an atom.
  • Aufbau Principle
    • Must be filled from the lowest energy to the highest energy level.
  • Hund's Rule
    • Must be filled singly before being paired.
  • Pauli's Exclusion Principle
    • No 2 electrons can have the same set of quantum numbers.
  • Chemical Bond - is the force of attraction that holds 2 atoms together.
  • Chemistry is the study of matter.
  • Law of Conservation of Mass
    • Proposed by Antoine Lavoisier.
    • States that matter is neither created nor destroyed
  • Law of Definite Composition/Proportions
    • Proposed by Joseph Proust
    • A compound is made up of the same proportions of each element.
  • Law of Multiple Proportions
    • Proposed by John Dalton
    • When 2 elements combine to form two or more compounds.
  • Lewis Electron Dot Symbol
    • A method to represent valence electrons of elements.
  • Noble Gases
    • The most stable atoms
    • Doesn't form chemical bonds with other atoms.
  • Octet Rule
    • States that an element must lose, gain, or share 8 electrons in its valence shell during chemical bonding.