Unit 2: Energy levels

Question 1

What are shells and first ev number called

Answer 1

Quantum number and ionisation energy

Question 2

what determines the colour of light

Answer 2

when an electron de excites the larger the drop in quantum number the larger the photon released. the light is more blue shifted due to higher frequency

Question 3

Describe excitation

Answer 3

since electrons can only exist on an energy level, electrons only absorb the correct amount of energy to get them to one of the energy levels- it will either absorb all of the energy or non of it. can be done through photoexcitation or electrical excitation (electron)

Question 4

J–>eV

eV–>J

Answer 4

/ 1.6x10^-19

*1.6x10^-19

Question 5

What is the photoelectric effect

Answer 5

Materials that emit electrons when light is shined onto them due to ionisation energy being met- they become electrically conductive. Energy determined by the frequency of light brightness effects amount of electrons

Question 6

What are the units of E=hf=hc/lambda

Answer 6

E-J eV
H- planks constant Js
Lambda- wavelength of light m
F- frequency of photon- Hz
C- the speed of light in a vacuum m/s

Question 7

What is line spectra?

Answer 7

since deexcitations have different energies depending on the difference in quantum numbers the resultant photons will have different frequencies. line spectra show us the spectrum of visible light produced. different atoms have unique line spectra

Different electron and protons different energy levels different energy photons different frequency different wavelengths of light

Question 8

What is Plank’s constant?

Answer 8

A constant the links the energy a wave/partial has to its frequency.- the frequency of a photon is related to its energy