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There are two primary mechanisms that broaden spectral emission (or absorption) lines: Doppler broadening and collision-induced broadening.
Doppler broadening occurs because of the relative thermal motions of the molecules in a gas. Simply put, the molecules are all bouncing off each other, so some are moving towards you and some away, some fast and some slow. Each molecule's spectrum is Doppler shifted by it's current velocity. The composite spectrum from all the individual molecules has its lines smeared out or broadened as a result. As you can guess, the amount of broadening depends on the temperature of the gas.
Collision-induced broadining, sometimes called pressure broadening, is is a result of the deformation of the molecules when they bounce off each other. For example, they may not be as symmetrical after a collision as they were before. These deformations perturb the quantum mechanical energy levels of the molecule, slightly shifting the frequencies of the emission or absorption lines. Just like Doppler broadening, the composite spectrum's lines are therefore broadened. This effect depends on both the pressure and temperature of the gas.
See spectralcalc for complete details and online simulations.
Starlight can be reddened by the Doppler Effect and by the gravity well (that light from a star finds itself in).
What else can I help you with?
Why would the absorption spectrum of each element have lines in the same places as in its emission spectrum?
The absorption spectrum of an element have lines in the same places as in its emission spectrum because each line in the emission spectrum corresponds to a specific transition of electrons between energy levels. When light is absorbed by the element, electrons move from lower energy levels to higher ones, creating the same lines in the absorption spectrum as the emission spectrum. The frequencies of light absorbed and emitted are the same for a specific element, resulting in matching lines.
The spectrum produced by glowing high-density gas is an a bright line emission b dark line absorption c chemical composition d temperature c continuous?
a Edit: The question is very mixed up, but I think I get the idea. It's obviously an emission spectrum. Because it is a high density gas the spectrum should be CONTINUOUS.
Who created the hydrogen line emission spectrum?
The hydrogen line emission spectrum was discovered by physicists Johann Balmer, Johannes Rydberg, and Niels Bohr. They observed that hydrogen gas emitted specific wavelengths of light, which formed a distinct spectrum now known as the Balmer series.
What is a line spectrum used for?
The line spectrum is usually used to sort out the atomic fingerprint as the gas emit light at very specific frequencies when exposed to the electromagnetic waves. The electromagnetic waves are usually displayed in form of the spectral lines.
Why line spectrum is called finger print spectrum?
It is unique to a specific atom. The emission spectrum of sodium, for example, has two characteristic lines close together in the yellow part of the spectrum, which cannot be found in any other atom. Each line in a spectrum relates to a change in electron state or level.
Which element did Bohr study the line emission spectrum of?
Niels Bohr studied the emission lines of Hydrogen.
Is an atomic emission spectrum a continuous range of colors?
No, an atomic emission spectrum is not a continuous range of colors. It consists of discrete lines of specific wavelengths corresponding to the emission of light from excited atoms when they return to lower energy levels. Each element has a unique atomic emission spectrum due to its unique arrangement of electrons.
The lines in the bright line spectrum of an atom are due to what?
The atomic line spectrum comes from the emission of atoms of different elements that are in an excited state. Each element has its own unique atomic emission spectrum.
Why would the absorption spectrum of each element have lines in the same places as in its emission spectrum?
The absorption spectrum of an element have lines in the same places as in its emission spectrum because each line in the emission spectrum corresponds to a specific transition of electrons between energy levels. When light is absorbed by the element, electrons move from lower energy levels to higher ones, creating the same lines in the absorption spectrum as the emission spectrum. The frequencies of light absorbed and emitted are the same for a specific element, resulting in matching lines.
The spectrum produced by glowing high-density gas is an a bright line emission b dark line absorption c chemical composition d temperature c continuous?
a Edit: The question is very mixed up, but I think I get the idea. It's obviously an emission spectrum. Because it is a high density gas the spectrum should be CONTINUOUS.
Is the spacing between the lines in the spectrum of an element constant or does it vary?
The spacing between the lines in the spectrum of an element are constant. This is called the emission spectrum of an element. Each element has a unique emission spectra that will be the same each time.
What causes the lines in an atomice spectrum?
The lines in an atomic spectrum are caused by the emission or absorption of photons as electrons move between different energy levels within the atom. Each line corresponds to a specific energy transition, and the distinct set of lines is unique to each element, making them a fingerprint for identifying elements.
Who created the hydrogen line emission spectrum?
The hydrogen line emission spectrum was discovered by physicists Johann Balmer, Johannes Rydberg, and Niels Bohr. They observed that hydrogen gas emitted specific wavelengths of light, which formed a distinct spectrum now known as the Balmer series.
How can you Distinguish absorption spectrum from emission spectrum?
Emission spectra are bright-line spectra, absorption spectra are dark-line spectra. That is: an emission spectrum is a series of bright lines on a dark background. An absorption spectrum is a series of dark lines on a normal spectrum (rainbow) background.
What does the term bright line spectrum mean?
A bright line spectrum refers to the pattern of distinct and bright lines of different colors that are produced when an element is excited and emits light. Each element has a unique bright line spectrum that can be used to identify the element through spectroscopy.
What do Each of the colored lines in hydrogen's emission spectrum corresponds with?
Each colored line in hydrogen's emission spectrum corresponds to a specific transition of an electron between energy levels in the hydrogen atom. The wavelengths of these lines are unique to each transition, creating a distinct pattern that can be used to identify elements and their energy levels.
What are Frequencies of light emitted by an element called?
"Spectrogram" is a word used to describe the set of specific characteristic frequencies of light which are emitted by a given chemical element when it is sufficiently excited by heat or by some other means.Alternatively, a scientific technique known as "spectroscopy" can be used to identify the elements in some matter of unknown composition and also the emission spectra of molecules can be used in chemical analysis of substances.Because each element's emission spectrum is unique, the "emission spectrum" of a chemical element or chemical compound can be used to help identify what it is. The "emission spectrum" is the name given to the relative intensity of each frequency of electromagnetic radiation http://www.answers.com/topic/emission-spectrum by the element's atoms or a compound's molecules when they are returned to a ground state.
