Flame Test - msmcgartland

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Name: _______________________
Date: __________________________
Flame Test Lab
Objectives
In this lab students will learn about flame tests for qualitative element
identification.
Overall Expectations
B2. investigate matter, using various methods of qualitative analysis
B3. demonstrate an understanding of the basic principles of qualitative analysis of matter.
Materials
Barium nitrate
Calcium nitrate
Copper(II) nitrate
Lithium nitrate
Potassium nitrate
Sodium nitrate
Strontium nitrate
Bunsen Burner
Inoculation Loops
Safety
Copy all safety procedures onto a separate piece of paper
1. Tie long hair back.
2. Secure all loose clothing.
3. Never leave a lit Bunsen Burner unattended.
4. Leave the Bunsen Burner in the middle of the lab bench.
5. Wear goggles at all times.
6. Wash hands before leaving the lab.
First Aid Procedures
1. If you are burned, run burned area under cold water for 10-15 minutes or until pain subsides.
Cover the burn with sterile gauze.
2. If spilled on hands, wash thoroughly for 15 minutes.
3. If contact with eyes, flush at eye wash station for 15 minutes.
4. If inhaled, remove to fresh air. If not breathing, give artificial respiration.
5. If ingested, call poison control immediately. Rinse mouth with cold water. Give victim 1-2
cups of water or milk to drink. Induce vomiting immediately.
6. Always seek professional medical attention after first aid measures are provided.
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Flame Test Lab
Procedure
1. Light the Bunsen Burner. Adjust the Bunsen Burner to give a roaring blue flame.
2. Dip the inoculation loop into the sample container. Make sure that there is some liquid in the
inoculation loop.
3. Hold the loop at a 45 degree angle and place the loop into the flame. Do not leave the
inoculation loop in the flame too long.
4. Observe the colour of the flame and record your results in the given table. Repeat if you did
not catch the colour of the flame. Leave the loop for the next group.
5. Repeat for all salts. Please remember to not mix the inoculation loops.
Table 1: Results of metal nitrate flame tests
Metal nitrate
Colour of Flame
Barium nitrate
Calcium nitrate
Copper(II) nitrate
Lithium nitrate
Potassium nitrate
Sodium nitrate
Strontium nitrate
Unknown nitrate
Post Lab Questions
Answers the following questions in the space provided.
1. Most salts contain a metal and a non-metal. Look at the compounds that were tested and
determine what is responsible for the colour produced in the flame test for that salt. How can
you be sure your answer is correct? Explain.
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2. Could flame tests be useful in determining identities of metals in a mixture of two or more
salts? If so, what problems might arise? If not, why not? Explain your answer fully.
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3. What metal is present in the unknown? How was this determined?
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Flame Test Lab
Answers:
1. Most salts contain a metal and a non-metal. Look at the compounds that were tested and
determine what is responsible for the colour produced in the flame test for that salt. How can
you be sure your answer is correct? Explain.
2. Could flame tests be useful in determining identities of metals in a mixture of two or more
salts? If so, what problems might arise? If not, why not? Explain your answer fully.
3. What metal is present in the unknown? How was this determined?
Teacher Reference
Metal
Barium
Calcium
Copper
Lithium
Potassium
Sodium
Strontium
Flame Colour
Yellow-green
Orange-red
Green
Pink-red
Lilac-purple
Orange
Deep red
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