1) Unit 1 - Electromagnetic Spectra Flashcards
Put these in order of increasing energy
- microwaves
- UV
- x-rays
- infrared
- radio waves
- gamma rays
- visible
radio waves > microwaves >infrared >visible >UV > x-rays
>gamma rays
what is the wavelength and what is its units
the distance between the highest point of waves
m or nm etc
as energy increase, wavelength ______
decreases
which of these two would have the bigger wavelength:
microwaves or x-rays
microwaves
what is frequency and what is its units
the number of waves that pass a fixed point in one second Hz or s-1
as energy increase, frequency ______
Increases
what is velocity and what is its units
the speed at which wavelengths travel at ms-1
what speed do all types of radiation travel at
3 x10^8
write a formula that shows the relationship between wavelength and frequency
f= c/λ
what can we conclude from this formula:
f= c/λ
as wavelength increase frequency decrease and vice versa
molecule x has a wavelength of light at 502 kjmoll-1
molecule y has a wavelength of light 234 kjmoll-1
which would have the greater frequency and why?
molecule x
why?
•molecule x has the greatest energy
•the greater the energy, the smaller the wavelength
•and the smaller the wavelength, the greater the frequency, molecule x would have the greater frquency
describe the emission spectra
- Energy absorbed results in electrons within an atom being PROMOTED to a higher energy level
- when the electron falls back to a lower or ground state energy level, energy is emitted
- The energy emitted corresponds to a wavelength of light
formula to calculate energy for 1 photon of light
E=hc/λ or E=hf
formula to calculate 1 mole of photons
E=Lhc/λ
formula to calculate wavelength when given its corresponding energy
λ=Lhc/E
