Flame Test Lab

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Flame Test Lab (p23-25)
Purpose:
Each element will produce a unique colour in a flame. The purpose of this lab is:
Day 1) to determine the colours produced by each metallic element provided
Day 2) to use the colours from day1 to determine the identity of the unknown compounds
Materials List – found on p23 of Chemistry 12 textbook
Add: well plate, wooden splint, distilled water
Samples to be tested:________________________________________________________
__________________________________________________________________________
Procedure:
Part 1 (testing solids):
1) Obtain your solid samples in a well plate (be sure to keep track of what samples are where in
your well plate – write this down).
2) Clean the nichrome wire first by rinsing it with lots of distilled water and drying with a paper
towel.
3) Hold the wire in the flame.
 If it adds no colour to the flame at the beginning it is clean and ready to use. When the
wire heats up and turns orange take it out of the flame and let it cool.
 If the wire does change the colour of the flame then dip it in a small beaker of
hydrochloric acid, then rinse with distilled water and dry in the flame. Repeat the
cleaning until the wire adds no colour to the flame.
4) Pick a small amount of your first solid sample up with the loop of the nichrome wire, hold the
loop in the flame and record your observations.
5) Clean the wire by first rinsing it with distilled water, drying with a paper towel then check the
wire in the flame as in step 3.
6) Repeat step 3-5 for all the solid samples
Part 2 (testing solutions):
1) Using the solutions and wooden splints provided, place the wet end of the wooden splint into
the flame for a maximum of 3 seconds. Record observations.
2) Return the wooden splint to the solution.
**Summarize your results from day 1 in a table. This should be included as your observations.
Day 2:
1) Test each unknown sample as you did in part one. Record the observations.
Conclusion
1) Compare your results from solid sodium chloride and solid sodium nitrate; what do they have
in common? What does this indicate about the samples?
2) Compare your results from solid sodium chloride and the sodium chloride solution; what do
they have in common? What does this indicate about the samples?
3) Analyze your observations and identify the metallic elements present in the unknown samples.
4) Using your results identify the metallic element in each flame in figure 1 p24.
5) What errors or problems did you encounter with this lab? How sure are you of your results?
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