(a) electromagnetic radiation and atomic spectra Flashcards
What is wavelength?
The distance between adjacent crests (or high points) in a wave.
How is wavelength usually measured?
In metres.
What unit is wavelength preferred to be calculated in by chemists?
Nanometres
How is metres converted into nanometers?
By multiplying by 10 to the power -9.
What is the symbol for wavelength?
Lambda.
What is frequency?
The number of wavelengths that pass a fixed point in one second.
What is the symbol for frequency?
f.
How is frequency measured?
1/time
What unit is frequency measured in?
S^-1
What is the unit also known as when related to frequency?
Hertz
On the electromagnetic spectrum radiation with a short wavelength will have what type of frequency?
High.
What does a long wavelength mean for the frequency?
It will be low.
What do all types of electromagnetic radiation travel at?
The same velocity in a vacuum.
What is the velocity which all electromagnetic radiation travel at?
3.00x10^8 ms-1
What symbol is velocity denoted by?
c
What is the relationship between frequency, velocity, and wavelength?
f=c/lambda or c=f x lambda or lambda=c/f
What type of nature does electromagnetic radiation have?
Duel nature.
What are the 2 natures of electromagnetic radiation?
Wave motion and streams of photons.
What happens to the electrons in a substance when it absorbs or emits a photon?
It will gain or loose energy.
If photons have (high energy radiation) (short wavelength) what does this mean for their energy?
It is high.
What is the energy carried by a photon related to?
Its frequency.
What is energy denoted by?
E
What does E equal?
E=hf
What is h?
Plancks constant.
What number is planks constant?
6.63x10^-34 J
What is energy measured in?
Joules.
What measurement is more useful for energy when in chemistry? (energy)
Kilojoules.
What does L equal? (look at deck)
Arogandros constant.
What is arogandros constant used for?
Used to determine the number of atoms per mole.
What number is arogandros constant?
6.02x10^23
What equation is used to determine the energy per mole of photons?
E=hLf/
1000
