1. What gives gas-filled lights their colors?
CHEMISTRY & YOU
What gives gas-filled lights their colors?
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2. Light and Atomic Emission Spectra
The Nature of Light
By the year 1900, there was enough experimental evidence to convince scientists that light consisted of waves.
The amplitude of a wave ______
_____________________________
The wavelength, represented by  (the Greek letter lambda), ____ ______________________________________________________.
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3. Light and Atomic Emission Spectra
The frequency () and wavelength () of light are _________________ proportional to each other. As the wavelength ________________, the frequency ____________________.
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4. Light and Atomic Emission Spectra
The Nature of Light
According to the wave model, light consists of electromagnetic waves.
_________________________________
includes radio waves, microwaves, infrared waves, visible light, ultraviolet waves, X-rays, and gamma rays.
All electromagnetic waves travel in a vacuum at a speed of _______________m/s.
This is the speed of light, represented by c.
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5. Light and Atomic Emission Spectra
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6. Light and Atomic Emission Spectra
The energy absorbed by an electron for it to move from its current energy level to a higher energy level is ___________________ to the energy of the light emitted by the electron as it drops back to its _______________ energy level.
The wavelengths of the spectral lines are characteristic of the element, and they make up the _________________________________ of the element.
No two elements have the same __________________
_____________________________.
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7. An Explanation of Atomic Spectra
When an electron has its lowest possible energy, the atom is in its _________________.
In the ground state, the principal quantum number (n) is 1.
Excitation of the electron by absorbing energy raises the atom to an _______________ state with n = 2, 3, 4, 5, or 6, and so forth.
A quantum of energy ___________________
____________________________________________________________________________
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8. CHEMISTRY & YOU
The glass tubes in lighted signs contain helium, neon, argon, krypton, or xenon gas, or a mixture of these gases. Why do the colors of the light depend on the gases that are used?
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