line spectrum

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line spectrum

A scientist observes a line spectrum through a spectroscope in the laboratory.

Definition

Noun: A line spectrum is an optical spectrum consisting of distinct, bright or dark lines at specific wavelengths, rather than a continuous band of colors. It is produced when atoms or ions in an excited state transition to a lower energy level, emitting or absorbing photons of very specific energies (and thus wavelengths).

Usage

A line spectrum is a fundamental concept in physics and chemistry, used to identify elements. * Scientists analyze the line spectrum of a star to determine its chemical composition. * The characteristic line spectrum of hydrogen includes a prominent red line. * In the laboratory, a spectroscope is used to observe the line spectrum emitted by a gas.

Advanced Usage
  • Emission line spectrum: A spectrum showing bright lines against a dark background, created when excited atoms emit light.
    • The neon sign's glow, when passed through a prism, produces a distinctive emission line spectrum.
  • Absorption line spectrum: A spectrum showing dark lines within a continuous spectrum, created when atoms absorb specific wavelengths from a background light source.
    • The Sun's spectrum is an absorption line spectrum, with dark Fraunhofer lines indicating elements in its outer atmosphere.
Variants and Related Words
  • Spectrum (n): The entire range of wavelengths of electromagnetic radiation.
  • Continuous spectrum (n): A spectrum that shows an unbroken sequence of colors or wavelengths, typically produced by hot, dense objects like solids or high-pressure gases. This contrasts with a line spectrum.
  • Band spectrum (n): A spectrum consisting of groups of closely spaced lines, typically produced by molecules.
Synonyms
  • Atomic spectrum
  • Discrete spectrum
Antonyms
  • Continuous spectrum
Related Phrases and Concepts
  • Spectral line: An individual bright or dark line within a line spectrum.
    • Each spectral line corresponds to a specific electronic transition within an atom.
  • To produce a line spectrum: The action of generating this type of spectrum.
    • Heating a sample of sodium in a flame will cause it to produce a characteristic yellow line spectrum.
line spectrum

A scientist observes a line spectrum through a spectroscope in the laboratory.

Noun
  1. a spectrum in which energy is concentrated at particular wavelengths; produced by excited atoms and ions as they fall back to a lower energy level