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known solution into designated well.
2. Obtain latex gloves; retrieve a beaker filled with about 10 mL of 6.0 M HCI and a nichrome wire loop. Light the Bunsen burner and be sure to adjust the flame to low.
3. After moving on to each test, be sure that the nichrome wire is clean so you don't contaminate the solutions. Clean the wire by rinsing it in distilled water using the wash bottle over the sink. Then dip it into the 6.0 M HCl Solution. Place in the flame for a few moments representing the control of the clean wire, you should see this after every trial.

4. *TEST SODIUM LAST as it has strong color which may affect other results. Dip the clean wire into one solution and place it in the burner flame and observe, record your observations in the data table 1. Clean the wire and repeat this step with the rest of the known solutions.
5. Obtain 3 unknown solutions from your teacher and repeat step 4 for each. Record observations in data table 2.
6. Turn off the Bunsen burner and clean up your work area, be sure to wash your hands before leaving.

Observations
DATA TABLE 1 FLAME TESTS OF KNOWN SOLUTIONS

Salt Solution Color
Barium Nit. (BA(NO3)2) yellow
Lithium Nit. (LiNO3) red
Strontium Nit (Sr(NO3)2) Red (lighter)
Potassium Nit. (KNO3) Purple
Copper Nit. (Cu(NO3)2) Green
Calcium Nit. (Ca(NO3)2) Pink
Sodium Chloride (NaCl) Orange

DATA TABLE 2 TESTS OF UNKNOWN SOLUTIONS

Unknown Color
A Red
B Red
C Pink

Analysis and Conclusion Questions:

1. The metallic ions present in the unknown solutions are Lithium in A and B and Calcium in C.

2. The color of each ion is the combination of the wavelengths in the transition. Barium nitrate and calcium nitrate both produce a pinkish color, and thus are some of the shorter wavelengths. Strontium nitrate produces a red color, while lithium nitrate puts off a red-orange color, thus also having the longest wavelengths. Copper (II) nitrate is a light violet, so it is one of the shorter wavelengths. Lastly is potassium nitrate, which puts off a yellow color, and lies in the middle of the visible spectrum, therefore, being a medium wavelength.

3. The visible spectrum ranges from red to indigo, covering the entire rainbow. Red is measured as the longest length at 700 nm, while pink is measured at the least at 400 nm. In between lie the green and blues, which lines are 500-600 nm in length.

Applications:

1. The yellow flame around the point of heating indicates that the solution is most likely potassium nitrate. The yellow flame also means that the wavelength is

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