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Unformatted text preview: Name: Amia Cumplido Chem 10, Section: Prelab Assignment: Flame Tests of Metal Cations
1. In this lab, you will perform flame tests of several different metal cations. The characteristic colors observed
are due to emitted electromagnetic radiation from the excited metal cations.
a. In this lab, how do the metal cations become "excited"?
The heat of the flame converts the metal ions into cations which become excited and emit visible light. b. Circle the correct responses to complete the following statement:
EM radiation is emitted when electrons make transitions from low / high to low / high energy levels.
2. In a flame test, the element Boron emits EM radiation that is predominantly green in color.
a. Use the Table in the Procedure to obtain the wavelength of this emitted radiation (in nm). Then convert this
wavelength from nm to m.
RED 701.0 nm = 701.0 x 10¯9 m = 7.010 x 10¯7 m
RED ORANGE 622.0 nm. x 10¯9 m = 6.220 x 10¯7 m
ORANGE 609.0 x 10¯9 m = 6.090 x 10¯7 m
ORANGE YELLOW 587.0 x 10¯9 m = 5.870 x 10¯7 m Yellow-Green 577.0 x 10¯9 m = 5.770 x 10¯7 m
Green 535.0 x 10¯9 m = 5.350 x 10¯7 m
Green-Blue 492.0 x 10¯9 m = 4.920 x 10¯7 m b. Calculate the frequency of this emitted green radiation, in s-1. Show your work.
v= (3.0 x10^8 m/s)
(4.861 x 10^-7 m) V=6.17x10^14 s-1 c. Calculate the energy of this emitted green radiation, in J. Show your work.
E=3.54 × 10^ −19J
E = hf = hc/λ
E=3.537×10−19J 3. Circle the type of EM radiation that has the property indicated:
a. Higher energy: UV or Visible light?
b. Longer wavelength: Orange or Blue light?
c. Higher frequency: IR or Yellow light? Page 1 of 1 ...
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