Flame tests:

Question:

Our text-book says to burn 2M solutions for flame tests, and I have tried solids too, but IT DOES NOT WORK! Can you please tell me what you do, and what actually works?

Answer:

Buy flame test bottles (atomisers) from Haines Educational.
Use the following:
All 0.5 M. Copper sulfate, sodium chloride, potassium chloride, strontium chloride and calcium nitrate, though other soluble salts with the same cations will do.
The best results come from spraying the mist into the Bunsen burner flame from about 20 cm away, and positioning the bottle just below the top of the Bunsen burner, so that the mist goes up into the flame. The most common problem comes from the atomiser being too close to the flame when the mist is sprayed, which blows the flame out.
POP STICK METHOD: Soak pop sticks over-night in about 150mls of 2M solution and then either pull them out the next morning to dry out a bit or just give them to the students wet. Place sticks in a Bunsen flame.
Another method is to burn a small amount of the different salts on a DEFLAGRATING SPOON but this can sometimes spit so is really only suitable for a teacher demo.

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