Chemistry I
Ms. Gallegos
NAME: ___________________________________________ DATE:_________________ PERIOD:______
PRACTICE No. 5: FLAME TESTS
OBJECTIVE:
Students will perform and observe the result of some flame tests and be able to identify the metallic ions
forming twelve different salts.
INTRODUCTION:
Fame tests are qualitative tests used in chemistry. When an ionic compound is exposed to the flame of a gas
burner, a characteristic color (visible to the naked eye!) is given off and distinguished.
Flame colors in flame tests are produced by the movement of the electrons in the metal. For example, when a
sodium ion (Na+1) is heated, the inner electrons absorb energy and can jump into empty orbitals at higher
levels depending on the amount of energy a particular electron had absorbed from the flame. Because these
electrons are now at a higher and more energetically level, they are unstable and tend to fall back down to
where they belong. While doing so, the electrons release a certain amount of energy which would be seen as
light of a particular color.
PRELAB:
You MUST handwrite question and answer to these questions on your notebook.
Consult academic sites from Internet and your textbook, but DO NOT forget to cite the consulted
bibliography.
1. What are the flame tests? What are they used for in chemistry?
2. What atomic particles are responsible for the production of colored light?
3. What type of energy is involved in the flame test?
4. Why do different chemicals/substances emit different colors of light?
5. What metallic ions produce the following colors in a flame test? Draw a table to answer this question.
Carmine (Dark Red)
Yellowish Green
Purple
Brick Red
Pale Green
White
Orange
Blue
Yellow
Violet
6. Colorful light emissions are applicable to everyday life. Where else have you observed colorful light
emissions? Are these light emissions related? Explain.
SET of MATERIALS per TABLE:
EQUIPMENT
SUBSTANCES
12 plastic dishes (duly labeled)
12 cotton swab ends
150-mL beaker with water
1 forceps or tweezers
1 Bunsen burner
4 pairs of Goggles
Lithium chloride
Sodium chloride
Potassium bromide
Calcium chloride
Strontium nitrate
Barium chloride
Manganese (II) chloride
Iron (III) chloride
Cobalt (II) chloride
Nickel (II) chloride
Cupper (II) chloride
Bismuth (III) chloride
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PROCEDURE:
1. Make sure that each student in your table wears the goggles AT ALL TIMES while performing this practice.
2. Have ready on hand the TABLE OF OBSERVATIONS AND DATA; you must follow the order for the flame
tests displayed there. During the lab practice only record the observations for the flame color, later you
and your table partners can help each other with the other answers.
3. Ask the teacher/ lab assistant to turn the burner on and be careful while handling its flame. Never leave the
burner unattended while it is on.
4. Soak a clean and dry cotton swab in the distilled water of the beaker and then dip the wet swab into the
first salt (LiCl2) to be tested according to the order in TABLE OF OBSERVATIONS AND DATA. Take a
small amount of the salt!
5. Hold the prepared swab with the salt with the forceps (tweezers) and place it into the burner flame and
observe and record the flame color. Remember you are trying to determine what is taking place during
the flame test whereby various colors of light are being emitted. BE CAREFUL not to catch the swab on fire
nor have molten plastic clog the burner.
6. Repeat steps 4 and 5 for each of the other eleven salts using a new clean swab every time until you test
all of the twelve salts on the table.
TABLE OF OBSERVATIONS AND DATA.
SALT
FLAME COLOR
METAL’S SHORTHAND
ELECTRON CONFIGURATION
No. of VALENCE
ELECTRONS for METAL
METALLIC
CATION
1. LiCl2
2. NaCl
3. KBr
4. CaCl2
5. Sr(NO3)2
6. BaCl2
7. MnCl2
8. FeCl3
9. CoCl2
10. NiCl2
11. CuCl2
12. BiCl3
For your lab report, DO NOT forget to include in all the required sections and for…
* Data Collection section, include the typed and completed TABLE OF OBSERVATIONS.
* Results and Analysis section, include an analysis of the certainty of the experiment, citing sources or error
and their effect on the stated result.
* Conclusions section, include an interpretation of your results, an explanation of why the hypothesis was
either correct or incorrect, and a summary of the accomplishment of the objectives.
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