CLASS 8 · LEARNING KNOWLEDGE
Spectra and chemical elements – basic principles
How it works
Spectra are produced when light is split into its different colors by a prism or diffraction grating. There are continuous, emission, and absorption spectra. Each chemical element has a characteristic line spectrum that serves for identification. Astronomers use spectra to determine the chemical composition and properties of stars and other celestial bodies. The color and the lines in the spectrum provide clues about temperature, motion (Doppler effect), and chemical elements.
Note
Each chemical element produces a unique line spectrum that can be used to identify the element. Absorption and emission spectra differ in the way light is absorbed or emitted by matter.
Each chemical element produces a unique line spectrum that can be used to identify the element. Absorption and emission spectra differ in the way light is absorbed or emitted by matter.
An example
What does an emission spectrum of an element show?
An emission spectrum shows the colored lines characteristic of the element on a dark background. These lines are produced when excited atoms emit light of specific wavelengths.
Try it yourself now
50 Exercises
To the learning unit →Own explanation and own practice exercises by AmyMath. Subject reference framework: Astronomy. The topic assignment may vary by federal state.