0.1 Students can demonstrate proper safety.
0.3 Students analyze and interpret data to
draw conclusions
2.1 Understand how the electrons are arranged
in the atom and can apply this concept to explain
the properties of elements
Name: _______________
Lab Partners: _______________
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Flame Test Lab
Purpose: To observe and identify metallic ions using flame tests.
Background: Have you ever wondered why a candle flame is yellow? The characteristic yellow of a candle flame comes
from the glow of burning carbon fragments. The carbon fragments are produced by the incomplete combustion
reaction of the wick and candle wax.
When elements, such as carbon, are heated to high temperatures, some of their electrons are excited to higher energy
levels. When these excited electrons fall back to lower energy levels, they release excess energy in packets of light
called photons. The color of the emitted light depends on its energy. Blue light is more energetic than red light, for
example. When heated, each element emits a characteristic pattern of light energies, which is useful for identifying the
element. In this lab, you will perform the flame tests in order to identify several metallic elements.
Materials:
Safety goggles, Bunsen burner, Calcium nitrate: Ca(NO3)2
Potassium nitrate: KNO3
Sodium nitrate: NaNO3
Barium nitrate: Ba(NO3)2
Strontium nitrate: Sr(NO3)2
Copper (II) chloride: CuCl2
Lithium carbonate: Li2CO3
Wood splints
2 Beaker
Safety: The salts used in this lab are TOXIC! No eating or drinking in the lab. Wash your hands when you are done with
your lab. Be sure to clean your lab station when you are done.
Procedure:
1. Make the room dark.
2. Your teacher will perform the flame test for the control and the calcium nitrate (Ca(NO3)2) for you. Record the
colors observed in the data table.
3. Get 2 beakers and fill them halfway with water.
4. Gather 9 wood splints for your group.
5. Set up a Bunsen burner and start the flame. Make sure the flame is blue, not orange. Adjust the lever on the
bottom of the Bunsen burner to make the flame blue.
6. Quickly dip a splint into one beaker of water. You want the splint to be damp, not dripping wet. Then, dip the
damp splint into a beaker containing one of the salts. Make sure that a few grains of the salt stick to the splint.
7. Place the splint into the flame. When you have seen the flame color, put the flaming splint into the second
beaker with water to put it out. Record the color of the flame observed in the data table.
8. Repeat steps 6 and 7 with a NEW splint for each salt and one unknown.
9. Use your results to identify the unknowns and record them in the data table.
10. Throw out all the used splints from the waste beaker.
11. Clean your lab station well.
Results:
Element, Ion
Control (no ions)
Calcium, Ca +2
Potassium, K +
Sodium, Na +
Barium, Ba +2
Strontium, Sr +2
Lithium, Li +
Copper (II), Cu +2
Unknown #1
Identity:
Unknown #2
Identity:
Flame color
Questions: Answer the following questfions in the space provided. Use complete sentences!
1. Which elements gave the most easily identified colors? Explain.
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2. Which elements are the least easily identified? Explain.
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3. Would flame tests be useful for detecting metal ions in a MIXTURE of metal ions? Explain your reasoning.
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4. We have seen a lot of colors today in lab. What is happening to the electrons in these atoms to produce light?
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5. The energy of colored light increases in the following order: red (lowest), orange, yellow, green, blue, violet
(highest). List the ELEMENTS tested in this lab from lowest to highest energy from the different light emitted.
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