Flame test
From Sciencemadness Wiki
This article is a stub. Please help Sciencemadness Wiki by expanding it, adding pictures, and improving existing text.
|
A flame test is an analytical procedure that can determine the presence of certain elements.
Contents
- 1 Procedure
- 2 Flame colors
- 2.1 Azure
- 2.2 Bluish-green
- 2.3 Brick red
- 2.4 Carmine
- 2.5 Crimson red
- 2.6 Emerald
- 2.7 Feeble green
- 2.8 Gray
- 2.9 Light blue
- 2.10 Orange
- 2.11 Pale blue
- 2.12 Pale green
- 2.13 Pink
- 2.14 Pure green
- 2.15 Purple
- 2.16 Red
- 2.17 Red-violet
- 2.18 Scarlet
- 2.19 Silvery-white
- 2.20 Violet
- 2.21 White
- 2.22 Yellow
- 2.23 Yellowish-green
- 3 Spectroscopy
- 4 References
Procedure
A flame test is carried out by placing a sample on a clean wire (commonly made out of platinum or nichrome), and placing it in a hot non-luminous flame (one that does not exhibit black-body radiation).
Flame colors
Azure
- Copper halides (copper(II) chloride)
- Bismuth
Bluish-green
- Phosphates with sulfuric acid
- Phosphorus
- Zinc metal
Brick red
Carmine
- Lithium (violet through blue glass, invisible through green glass, masked by barium)
Crimson red
- Radium
Emerald
- Copper non-halides
- Ytterbium metal powder
Feeble green
- Ammonium
- Antimony
Gray
Light blue
Orange
Pale blue
Pale green
- Antimony
Pink
- Samarium metal
Pure green
Purple
Red
Red-violet
Scarlet
- Strontium (violet through blue glass, yellowish through green glass, masked by barium)
Silvery-white
Violet
- Potassium (masked easily)
White
Yellow
- Sodium (masks everything, invisible through blue glass)
Yellowish-green
Spectroscopy
A mad scientist with a more technical bent can improve this technique by building a simple spectroscope, which decomposes the light from the flame into a spectrum. The advantages of spectroscopy is that it does not require any colored glass, all spectral lines are visible separately without them.