GENERAL CHEMISTRY 1

• it is the distance between identical point in successive waves

  wavelength
• frequency - number of waves pass through a particular point in a second
• amplitude - vertical distance from the midline of a wave to the peak or through
• wave - vibrating disturbance by which energy is transmitted
• Quantum theory - also known as quantum mechanics, is the branch of

  physics that describes the behavior of matter and energy at the

  smallest scales
• speed of the wave formula - lambda x frequency
• James Clerk Maxwell (1873), proposed that visible light consists of electromagnetic waves.
• Electromagnetic radiation is the emission and transmission of energy in the form of electromagnetic waves.
• Speed of light (c) in vacuum = 3.00 x 108 m/s
• All electromagnetic radiation

  lambda x frequency = c
• 3 mysteries of classical physic

  1. Ultraviolet catastrophe
  2. Photoelectric effect
  3. Atomic Spectra
• Classical physics predicted that the intensity of blackbody radiation would increase indefinitely with increasing frequency, leading to what was known as the ultraviolet catastrophe.
• ULTRAVIOLET CATASTROPHE WAS SOLVED BY PLANCK 1901
• blackbody emits all radiation of all wavelength
• Planck stated that Energy (light) is emitted or absorbed in discrete units(quantum).
• The photoelectric effect is a phenomenon where electrons are emitted

  from a material (such as a metal) when it is exposed to electromagnetic radiation, typically in the form of light or ultraviolet radiation.
• photoelectric effect catastrophe was solved by einstein 1905
• Einstein proposed that light consists of discrete packets of energy called photons, and the energy of these photons determines whether electrons are ejected from the material.
• Light has both:

  1. wave nature

  2. particle nature
• e- - can only have specific (quantized) energy values
• According to classical electromagnetic theory, a continuous spectrum should be emitted or absorbed by atoms.
• Series in Atomic Hydrogen Emission Spectrum - lyman nf-1, balmer nf-2, pashen nf-3, brackett nf-4
• spectrum region of series - ultraviolet, visible light and infrared