Flame Test Lab Page

Final Lab Report Must Be in Your Lab Notebook!

Flame Test Lab Questions and Calculations

Setup in Lab Notebook:

In your lab notebook you must have the Purpose, Hypothesis, Materials, Safety and Procedure.

Prepare a data table for your results.

1. Use the table below to record the approximate wavelength of light emitted for each known metal ion in the Results Table.

2. Convert each wavelength in the Results Table from nanometers to meters. Show all calculations!!!
    Record your new values in the Results Table.  Conversion Factor: 1 meter= 1 x 10^-9 nm

3. The characteristic color of the sodium flame is due to two closely-spaced energy transitions.  Use the following equation to calculate the average energy (E) corresponding to the observed flame color for each metal. Show all calculations!
Record all values in the Results Table.
Equation:  E= (6.26 x 10-34 J·sec)(2.998 x 108 m/sec) ÷ your wavelength in meters for each metal

Conclusion:

1a. What evidence is there from your results that the characteristic color observed for each compound is due to the metal ion in each case? 

b. Describe an additional test that could be done to confirm that the color is due to the metal ion.

2a. A glass rod was heated in a burner flame and gave off a bright yellow flame. 

b. What metal ion predominates in the glass rod?

3. The alkali metals cesium and rubidium were discovered based on their characteristic flame colors.  Cesium is named after the sky and rubidium after the gem color.  What colors do you think these metals give off when heated in a flame?

Colors and Wavelengths
Violet	410 nm
Blue	470 nm
Blue-Green	490 nm
Green	520 nm
Yellow-Green	565 nm
Yellow	580 nm
Orange	600 nm
Pink	625 nm
Red	650 nm

Discussion/Conclusion Questions

Your discussion/conclusion should consist of the following:

A. Summarize procedure in a couple sentences.

B. Describe results (data) in great detail.  Explain the relationship between the data collected and the conclusion or new idea that is proven by the data.  What connection can be drawn by the data or graph to any theories in class? 

C. Explain how your flame tests relate to the chemistry of fireworks.

D. Explain how your flame tests involved incandescence and luminescence.

E. Explain what happened to the electrons that allowed you to see the colors each metal gave off.

F. Discuss any errors made and how mistakes affected results

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