by Callie Gray

Created on: May 24, 2008

Full Lab Report
Callie Gray

Introduction:
In the flame test lab we undergo flame tests, a quick method of producing the characteristic colors of metallic ions. The loosely held electrons are easily excited in the flame and this energy emitted in the visible portion of the spectrum enables electrons to return to lower energy, producing a colored flame. This color is a combination of the wavelengths of each transition used to determine the identity of the ion. In the lab we are doing just this, testing different ions to see what color they produce. With the flame, the wire loop and our samples of ions, we should be able to identify each metallic ion by the emitted colors.

Pre-Lab Questions
1. Write out the electron configurations for each of the metallic ions to be tested in this investigation.
A) Ba2+ = Xe
=1s22s22p63s23p64s23d104p65s24d25p6
B) Cu2+ = Co
=1s22s22p63s23p64s233d7
C) Li+ = He
=1s2
D) K+ = Ar
=1s22s22p63s23p6
E) Sr2+ = Kr
=1s22s22p63s23p64s23d104p6
F) Ca2+ = Ar
=1s22s22p63s23p6
G) Na+ = Ne
=1s22s22p6

2. The flame tests indicate producing the characteristic colors of metallic ions. The color is a combination of the wavelengths of each transition and may be used to determine the identity of the ion

3. A metallic ion produces characteristic color in a flame test because the loosely held electrons of a metal are easily excited in the flame of a lab burner. The emission of energy in the visible portion of the spectrum as those electrons return to lower energy produces a colored flame.

4. Wavelengths that correspond to the visible spectrum are visible light. The color that has the shortest wavelength is cosmic rays. The color that has the longest wavelength is radio wave.

5. When handling 6.0 HCI you should wear your goggles and lab apron at all times.

6.It's important to use a clean nichrom wire for each test because if you use a dirty wire you can contaminate your samples.

Materials:
- Chemical splash goggles
-Laboratory apron
-Latex gloves
-Well plate
-Marker pen
*Solutions of the following salts:
-Barium nitrate (Ba(NO3)2)
-Copper nitrate (Cu(NO3)2)
-Strontium nitrate (Sr(NO3)2)
-Lithium nitrate (LiNO3)
-Potassium nitrate (KNO3)
-Sodium chloride (NaCl)
-Calcium nitrate (Ca(NO3)2)
-Nichrome wire loop
-Beaker, 50-mL
-Hydrochloric acid, 6.0 M
-Lab burner
-Wash bottle with distilled water
-3 unknown solutions

Procedure:
1. Put on goggles and lab apron and secure any other safety precautions. Get a well plat and Label 7 wells with the given names of the known solutions. Put dropperful of each

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