What scientific principle are spectroscopic techniques based on?
Under certain conditions a substance can absorb or emit electromagnetic radiation in a characteristic way
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Describe absorption spectra
Black (dark) lines on a coloured background
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Describe emission spectra
Coloured lines on a black (dark) background
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Name an example of a continuous spectra
White light - contains all visible wavelengths
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What does an intense line on an atomic spectra indicate?
The abundance of the element
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What is the Balmer series?
Hydrogen emission spectrum in visible light
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What is the Lyman series?
Hydrogen emission spectrum in ultraviolet light
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What is the name of the two theories used to describe the behaviour of light?
The wave theory and the particle theory
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Which equation is used to calculate the speed of a wave?
Speed of light = wavelength x frequency
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What is the speed of light?
300,000,000 ms-1
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According to the particle theory of light, what is light regarded as?
A stream of tiny packets of photons
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Which equation is used to calculate the energy of a photon
Energy of a photon = Planck constant x Frequency
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What is the value of the Planck constant?
6.63 x 10 (^-34) Js-1
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What happens to electrons in an atom during an emission spectrum?
When an atom becomes excited, electrons jump into higher energy levels. Then, they drop back into lower levels and emit extra energy as EM radiation
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What happens to electrons in an atom during an absorption spectrum?
Light is absorbed by the atom. Electrons have been raised to higher levels without then dropping back again
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What were the four main points of Bohr's theory?
The electron in the hydrogen atom exists in definite energy levels. A photon of light is emitted/absorbed when the electron changes from one energy level to another. The energy of the photon is equal (delta E). Since E=hv, (delta E) = hv
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What does an electron possess?
Definite quantities of energy (quanta). The electron's energy cannot change continuously and only allows certain values
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What are the flame colours for the following metal ions: Li+, Na+, K+, Ca2+, Ba2+, Cu2+?
Crimson (bright red), yellow, lilac, brick red, apple green, blue green
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Other cards in this set
Card 2
Front
Describe absorption spectra
Back
Black (dark) lines on a coloured background
Card 3
Front
Describe emission spectra
Back
Card 4
Front
Name an example of a continuous spectra
Back
Card 5
Front
What does an intense line on an atomic spectra indicate?
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