Sodium is a common component or contaminant in many compounds and its spectrum tends to dominate over others. The test flame is often viewed through cobalt blue glass to filter out the yellow of sodium and allow for easier viewing of other metal ions.
Why is the test tube filled with water?
A test tube filled with water and upturned into a water-filled beaker is often used to capture gases, e.g. in electrolysis demonstrations. A test tube with a stopper is often used for temporary storage of chemical or biological samples.
What type of flame is used in laboratory?
A Bunsen burner, named after Robert Bunsen, is a kind of gas burner used as laboratory equipment; it produces a single open gas flame, and is used for heating, sterilization, and combustion. The gas can be natural gas (which is mainly methane) or a liquefied petroleum gas, such as propane, butane, or a mixture.
Where is the hottest part of a blue flame?
The inner core of the candle flame is light blue, with a temperature of around 1800 K (1500 °C). That is the hottest part of the flame.
How is a luminous Bunsen flame different from a clear blue flame?
The air-starved, fuel-rich, incandescent carbon soot filled luminous flame is a chemically different test environment than the clear blue flame. The bright orange / yellow luminosity can mask the color and visibility of the flame color from the test sample. What is the flame test and what are its applications?
Why does a luminous flame produce much light and soot?
Relatively non-luminous flames tend to be hotter, although there is no inevitability about it. To produce a strongly luminous flame, you must have particles present in the flame, and those usually come from incomplete combustion of the thing being burned.
Why is HCl used in a flame test?
The flame test is used to visually identify an unknown metal or it’s ion based on the characteristic color it turns the flame of a Bunsen burner. The heat of the flame excites the electrons of the metals ions, causing them to emit visible light.
Can a platinum wire be used in a flame test?
Also, a platinum wire should be thoroughly cleaned before using it for a new flame test. A platinum wire is cleaned by dipping it into concentrated HNO3 and then placing it in the non luminous part of the bunsen flame. Otherwise, the perviously tested radicals will impart color to the flame, which may cause confusion.