Aug
Color Unknown
Posted in Yarn | No Comments »An unknown salt was tested in the flame and emitted yellow. Can you conclude that the Na salt ts? why?
The simple answer is yes, because the yellow light is typical of sodium which can be regarded as definitive proof of sodium. When an atom get 'excited' by the energy (the heat), then they will relax from energy emitting excited state that, in general it is in the form of light at a certain wavelength. The wavelength depends on the atomic structure of the atom that has was excited. Therefore, the atoms emit light on heating according to their atomic structure. Sodium emits a powerful light yellow (as shown by the light yellow sodium street). This idea is the basis of spectrophotometry. As the excited atom the electron jump a higher level of energy (think of it as the next orbit) and then when they cool, they jump back to the stable orbit and emit excess energy (often in the elecromagnetic light radiation, for example) The test flame is just a basic method of examination of light emitted by excited atoms and the yellow light of sodium is so special that it can be used to identify the presence of sodium in a compound. Other metals emit light at different wavelengths and so you can identify them by their color. Whereas, in other atoms emit light outside the visible specrum so you will not see with your eye. A method more accurate based on the test flame spectrophotometry, flame emission when a solution is passed through a hot flame and a photocell is used to measure the amount of light of a certain wavelength, which is calibrated against a solution standard quantity of a substance can be determined.