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Topic: Continuous v. line spectra  (Read 2779 times)

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Offline Foobarz

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Continuous v. line spectra
« on: November 13, 2011, 12:49:16 PM »
Ok so it says in my textbook (Chang, 8/e) that a heated solid produces a continuous spectrum. However, the emission spectra of atoms in the gas phase are line spectra (eg. light emission only at specific wavelengths) What I want to know is WHY?

Offline fledarmus

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Re: Continuous v. line spectra
« Reply #1 on: November 14, 2011, 08:02:21 AM »
I think you are looking at two different phenomena - black body radiation http://en.wikipedia.org/wiki/Black_body_radiation and atomic emission http://en.wikipedia.org/wiki/Atomic_emission


Offline CrimpJiggler

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Re: Continuous v. line spectra
« Reply #2 on: November 15, 2011, 08:42:17 AM »
Yeah black body radiation is when you heat something up so much is starts giving off the excess heat as light. Atomic emission (the kind you are probably talking about) is where an electron gains enough energy to jump to a higher orbital then emits that same amount of energy as it jumps back down to the lower orbital.

Offline vmelkon

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Re: Continuous v. line spectra
« Reply #3 on: November 15, 2011, 12:22:12 PM »
Yeah black body radiation is when you heat something up so much is starts giving off the excess heat as light. Atomic emission (the kind you are probably talking about) is where an electron gains enough energy to jump to a higher orbital then emits that same amount of energy as it jumps back down to the lower orbital.

When you heat a solid, what gives off light? Isn't it the electrons jumping from higher to lower energy level.

Offline fledarmus

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Re: Continuous v. line spectra
« Reply #4 on: November 15, 2011, 12:54:07 PM »
No, release of heat by a black body radiation is release of thermal energy - a change in the kinetic energy of the atoms rather than a decay of an excited electrical state.

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