UV-vis Spectroscopy
No description yet. This curated deck is ready for daily study.
Card preview (24)
What did Isaac newton show about light ?
Light can be split into colours
Tell me about electromagnetic spectrum ?
Humans can only detect a small part which is visible of the spectrum as visible light is only a small part of the spectrum which includes radio, infrared , UV , etc
What can light be?
Light can be both a wave or a particle
What is the symbol for Wavelength ?
Lambda which looks like a upside down Y
Definition of wavelength ?
It’s the distance between 2 equivalent linear points in successive cycles
What is the wavelength measured in ?
Cm , micrometer or nano metre
What is amplitude ?
It’s the maximum value reached by the wave in given direction over a cycle Eg from the middle of the line to the top point of the curve of the wave
What is frequency in terms of waves ?
It’s the number of waves passing a fixed point per second
What is the equation for frequency?
Frequency = the speed of the wave (V) / wavelength ( lambda )
What are the units for the speed of the wave (V) ?
M S-1
What is the units for wavelength ( lambda ) ?
Metres
What is the units for frequency?
Frequency is measured in SI units called hertz Hz and is equivalent to S-1
What would the equation for frequency be when you are dealing with with light ?
Frequency = C / lambda Where C is a constant of 3 x 10^8
What is spectroscopy ?
Its an analytical technique that examines how matter absorbs energy across the electromagnetic spectrum
What does matter mean ?
Like a physical thing
What does each region such as UV, light in the electromagnetic spectrum correspond to ?
Each regions which as light , UV , IR corresponds to an energy transition such as rotational, vibrational , electronic When matter absorbs energy
What does the absorption of energy by matter depend on ?
Chemical nature of molecules or atoms
What was Einsteins idea of light as a wave ?
He proposed that light isn’t just a wave but it can act as small packets of energy called photons Each photon has a specific amount of energy that depends on the colour ( frequency) of light
What colour of light does high energy photons give ?
Blue or UV light
What colour of light does low energy photons give ?
Red light
How does photons link to frequency ?
The higher the frequency eg the shorter the wavelength, the more energy the photons have so is directly proportional
What is the equation to link frequency and photon ?
E= Hf
What does h stand for ?
Planks constant which is 6.63 x 10 -34
How does energy of photon link to Wavelength ?
Energy of photon is inversely proportional to wavelength as shorter wavelength means higher frequency