Heisenberg Uncertainty Principle

Key Questions

  • Heisenberg contributed through his uncertainty principal.

    He stated that an electron's velocity and location can not possible be known simultaneously. The reason for this is because an electron is such a tiny tiny amount of mass, the act of observing it with any kind of light (radiation) would move the particle in a different direction/velocity.

    When you want to locate your phone across a room, you look at it and light bounces off of your phone to your eye. If you look at an electron, light (photons) hit the electron, thus moving it in a different direction and speed.

    The exact formula for calculating the uncertainty of an electron goes:
    Δx > h/4πmΔv

    Where Δx = the uncertainty
    h = 6.626 x 10-34 J-s
    m = mass of electron (9.109 x 10 -31 kg)
    Δv = the degree of certainty you are given (e.g. "speed is known to within 0.01m/s")

    Sometimes the uncertainty can be bigger than the atom itself which is why electrons have never been observed directly.

    Complete presentation in simple terms here: http://chemistry.tutorvista.com/organic-chemistry/werner-heisenberg-atomic-theory.html