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Ocean Optics Overture User Manual

Page 48

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Appendix A: Sample Experiments

40

000-20000-400-01-201108

 Stand and clamp
 Flame test wire loop
 Banana or dried banana chips
 Salts: LiCl, NaCl, SrCl

2

, CuCl

2

, BaCl

2,

CaCl

2

 1M HCl for cleaning the loop

Objectives:

 To show that flames test emissions are line spectra that can be identified by comparison with

reference line spectra.

 To use potassium salts and the reference library of emission lines to identify potassium in

bananas.

Procedure:

1. Set the spectrometer to Intensity mode. Use a 400 micron fiber optic or remove the fiber optic cable.

Caution

If you use the spectrometer without a fiber optic cable, you should take steps to
prevent chemicals from entering the entrance port. Use a small piece of plastic wrap
to cover the port.

2. Hold the fiber in a laboratory clamp about 30 cm from the flame.

3. Be careful not to have fluorescent lamps in the line of sight of the fiber. This will cause mercury

spectral lines. Use the mercury lines to check for these.

4. Use the Snapshot tool to freeze spectral lines.

5. Overlay the reference lines to identify the metal elements in salts.

Sodium contamination will show up as a line at 589nm.You can try to clean the flame test loop with HCl
to eliminate it, or just recognize it as contamination. Sodium contamination is a problem when looking at
flames by eye because the yellow is so bright that it masks other fainter colors. The spectrometer does not
have that problem because every wavelength is detected and displayed separately.