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Your interest is greatly appreciated. As a first step, let's clarify that flame tests as an analytical tool are obsolete. No professional chemist will use them to identify a given unknown sample. However, flame absorption and emission spectroscopy continuescontinue to be used routinely today at a more sophisticated level. There were so many elements discovered through flame emission that its demonstration is still worthwhile today. As for the cartoon flame test, I was simply referring to the Java app that depicted a fictitious flame test. It had some inaccurate atomic emission depictions as well as misleading electronic transitions "backed up" by the NIST database.

Flame tests of Group I, Group II, and some other selected elements should be performed using a platinum wire that has been dipped clean several times in HCl soln. Introduce the wire into the flame and heat it until no color appears in the flame. We all know that sodium is everywhere so this process ensures that the Pt wire is clean. Moreover, it is ensured that we use an oxidizing flame, that is, the flame should be very light blue to near-invisible with a clear blue cone inside. This is adjusted by checking the air flow to the Bunsen burner. Then one would dip the clean Pt wire in a concentrated solution of a chloride of Group I, II and some selected transition metals. Chlorides salts decompose and volatilize easily in a relatively low temperature flame of a Bunsen burner (methane and air) and immediately color the flame.

There are different levels of flame tests:

(a) At an elementary level, the flame is viewed with the naked eye and the flame color is noted.

(b) Next level is the use of cobalt blue glass to block sodium emission and sometimes iron contamination

(c) The third and perhaps the most effective level is to use a prism/grating spectroscope to watch the spectrum on a calibrated scale. However in that case, there must be a continuous supply of the sample to the flame. There are various methods to achieve that.

Your interest is greatly appreciated. As a first step, let's clarify that flame tests as an analytical tool are obsolete. No professional chemist will use them to identify a given unknown sample. However, flame absorption and emission spectroscopy continues to be used routinely today at a more sophisticated level. There were so many elements discovered through flame emission that its demonstration is still worthwhile today. As for the cartoon flame test, I was simply referring to the Java app that depicted a fictitious flame test. It had some inaccurate atomic emission depictions as well as misleading electronic transitions "backed up" by the NIST database.

Flame tests of Group I, Group II, and some other selected elements should be performed using a platinum wire that has been dipped clean several times in HCl soln. Introduce the wire into the flame and heat it until no color appears in the flame. We all know that sodium is everywhere so this process ensures that the Pt wire is clean. Moreover, it is ensured that we use an oxidizing flame, that is, the flame should be very light blue to near-invisible with a clear blue cone inside. This is adjusted by checking the air flow to the Bunsen burner. Then one would dip the clean Pt wire in a concentrated solution of a chloride of Group I, II and some selected transition metals. Chlorides salts decompose and volatilize easily in a relatively low temperature flame of a Bunsen burner (methane and air) and immediately color the flame.

There are different levels of flame tests:

(a) At an elementary level, the flame is viewed with the naked eye and the flame color is noted.

(b) Next level is the use of cobalt blue glass to block sodium emission and sometimes iron contamination

(c) The third and perhaps the most effective level is to use a prism/grating spectroscope to watch the spectrum on a calibrated scale. However in that case, there must be a continuous supply of the sample to the flame. There are various methods to achieve that.

Your interest is greatly appreciated. As a first step, let's clarify that flame tests as an analytical tool are obsolete. No professional chemist will use them to identify a given unknown sample. However, flame absorption and emission spectroscopy continue to be used routinely today at a more sophisticated level. There were so many elements discovered through flame emission that its demonstration is still worthwhile today. As for the cartoon flame test, I was simply referring to the Java app that depicted a fictitious flame test. It had some inaccurate atomic emission depictions as well as misleading electronic transitions "backed up" by the NIST database.

Flame tests of Group I, Group II, and some other selected elements should be performed using a platinum wire that has been dipped clean several times in HCl soln. Introduce the wire into the flame and heat it until no color appears in the flame. We all know that sodium is everywhere so this process ensures that the Pt wire is clean. Moreover, it is ensured that we use an oxidizing flame, that is, the flame should be very light blue to near-invisible with a clear blue cone inside. This is adjusted by checking the air flow to the Bunsen burner. Then one would dip the clean Pt wire in a concentrated solution of a chloride of Group I, II and some selected transition metals. Chlorides salts decompose and volatilize easily in a relatively low temperature flame of a Bunsen burner (methane and air) and immediately color the flame.

There are different levels of flame tests:

(a) At an elementary level, the flame is viewed with the naked eye and the flame color is noted.

(b) Next level is the use of cobalt blue glass to block sodium emission and sometimes iron contamination

(c) The third and perhaps the most effective level is to use a prism/grating spectroscope to watch the spectrum on a calibrated scale. However in that case, there must be a continuous supply of the sample to the flame. There are various methods to achieve that.

Source Link
ACR
  • 41.6k
  • 2
  • 66
  • 131

Your interest is greatly appreciated. As a first step, let's clarify that flame tests as an analytical tool are obsolete. No professional chemist will use them to identify a given unknown sample. However, flame absorption and emission spectroscopy continues to be used routinely today at a more sophisticated level. There were so many elements discovered through flame emission that its demonstration is still worthwhile today. As for the cartoon flame test, I was simply referring to the Java app that depicted a fictitious flame test. It had some inaccurate atomic emission depictions as well as misleading electronic transitions "backed up" by the NIST database.

Flame tests of Group I, Group II, and some other selected elements should be performed using a platinum wire that has been dipped clean several times in HCl soln. Introduce the wire into the flame and heat it until no color appears in the flame. We all know that sodium is everywhere so this process ensures that the Pt wire is clean. Moreover, it is ensured that we use an oxidizing flame, that is, the flame should be very light blue to near-invisible with a clear blue cone inside. This is adjusted by checking the air flow to the Bunsen burner. Then one would dip the clean Pt wire in a concentrated solution of a chloride of Group I, II and some selected transition metals. Chlorides salts decompose and volatilize easily in a relatively low temperature flame of a Bunsen burner (methane and air) and immediately color the flame.

There are different levels of flame tests:

(a) At an elementary level, the flame is viewed with the naked eye and the flame color is noted.

(b) Next level is the use of cobalt blue glass to block sodium emission and sometimes iron contamination

(c) The third and perhaps the most effective level is to use a prism/grating spectroscope to watch the spectrum on a calibrated scale. However in that case, there must be a continuous supply of the sample to the flame. There are various methods to achieve that.