Flame Test

Theresa Fichera                 Frazier Elementary School
                                4027 West Grenshaw Street
                                Chicago, Illinois 60624
                                (312) 534-6880

Objectives:

    The student will
      1.  view the spectra of various elements with and without a spectroscope.
      2.  understand that the color and spectral lines are determined by the 
          electron configuration of each element.
      3.  understand that the electrons emit photons after being energized in 
          some way and that we detect some of these photons as visible light.
      4.  view the colors emitted by various metallic salts as they are put into 
          a bunsen burner flame.
      5.  identify two unknown compounds containing some of these same metals.

Materials needed: (Class of 12)

      1.   power supply and elemental spectrum tubes
      2.   12 student spectroscopes
      3.   bunsen burners
      4.   metallic nitrate and metallic chloride solutions (.4M)
      5.   wooden splints
      6.   safety goggles
      7.   student worksheets
      8.   sparkler or a toy that gives off sparks

Strategy:

      1.   Ask students to identify energy entering sparkler toy.
      2.   Ask students to identify energy leaving sparkler toy.
      3.   Relate this information to the law of conservation of energy.
      4.   Review the Bohr model of the atom and electron shells.
      5.   Discuss energy in and energy out in terms of energy conversion.
      6.   Ask students to predict results of energizing a spectrum tube filled 
           with hydrogen gas.  
      7.   Energize the tube and have someone explain light in terms of the Bohr 
           model.
      8.   Change to a neon tube and repeat the process.
      9.   Discuss color differences in terms of electron configuration of two 
           different atoms.
     10.   Have students look at white light with a spectroscope and name the 
           colors seen.
     11.   Discuss colors as evidence of energy levels of emitted photons.
     12.   View both spectrum tubes with a spectroscope and discuss emission 
           lines.
     13.   Have students energize metallic salt solutions over a bunsen burner 
           flame and note the color of each metal.
     14.   Have students energize two "Unknown" metallic salt solutions and 
           identify them based on the colors noted in #13.
     15.   Ask the students how such information could be used in the fields of 
           astronomy and criminal investigation.