Arrangement of Electrons in the Atom 2

AAS

  • Light that emerges has certain wavelenghts missing i.e dark lines are observed in spectrum(AAS)
  • Emission spectrum consists of coloured lines against a dark background
  • Absorption spectrum consists of dark lines against a coloured background

Heisenburgs Uncertainty Principle

Uses of AAS

  • Detecting the presence of certain elements in materials dissolved in water & measuring the concentrations of these elements using an instrument called an atomic absorption spectrometer
  • Used in forensic science to test for gunshot residue

Wave nature of the electron

  • Louis de Broglie-all moving particles have a wave like motion associated with them
  • Impossible to measure both the velocity and position of the electron at the same time

Limitations

  • Heisenburgs Uncertainty Principle was in conflict with Bohrs theory i.e we can only refer to the probability of finding an electron in a region in space
  • Bohrs theory could not explain the splitting of certain lines in emission spectra and did not take into account the presence of sublevels

Orbitals

  • Region in space where there is a high probability of finding an electron
  • px py pz
  • Sublevel-subdivision of a main energy level and consists of one or more orbitals of the same energy
  • 2p sublevel consists of 3 p orbitals of the same energy