Atomic Phenomena

Question 1

Thermal Blackbody Radiation

Answer 1

All matter will emit electromagnetic radiation as long as the temperature is above absolute zero

Question 2

How do scientists approximate blackbody radiation?

Answer 2

Cavity radiation, which is the radiation produced in a cavity within a hot object

Question 3

Planck’s Constant

Answer 3

h = 6.63 X 10^-34 J s = 4.14 X 10^-15 eV s

Question 4

What does the blackbody curve show?

Answer 4

The blackbody spectrum is energy radiated plotted against light wavelength and it shows the amount of energy radiated as a function of wavelength. There is one wavelength were the maximum amount of energy radiates, dependent upon absolute temperature of the blackbody.

Question 5

Wien’s Displacement Law

Answer 5

λ(peak) T = constant = 2.90 X 10^-3 m K

Question 6

Stefan-Boltzmann Law

Answer 6

E(T) = σT^4
σ = 5.67 X 10^-8 J/ (s m^2 K^4)

Question 7

Photoelectric Effect

Answer 7

Electron expulsion after metal sheet hit with light of certain frequency discovered by Heinrich Hertz in 1887

Question 8

Threshold Frequency

Answer 8

The minimum frequency of light that ejects an electron dependent on the type of metal exposed

Question 9

Energy of the photon of light

Answer 9

E = hf = hc/ λ

Question 10

What type of light has higher energy?

Answer 10

Higher frequency/ shorter wavelength

Question 11

Maximum Kinetic Energy of Ejected Electron

Answer 11

KE = hf - W = hf - hf(threshold)

Question 12

Bohr Model of Hydrogen Atom

Answer 12

There are specific stable orbits of quantized energy where electrons do not radiate energy, where the energy is negative until reaching 0 eV and becoming unbound. The ground state of Hydrogen is -13.5 eV and E(n) = -13.6/ n^2 in Hydrogen

Question 13

Emission and Absorption of Light

Answer 13

1. Stable and discrete energy level
2. Electrons emit or absorb radiation ONLY during transition from one energy level to another
3. Electron absorbs a right frequency proton when moving to higher energy
4. Electron emits photon when moving to lower energy
   While emitting or absorbing photons, the frequency will allow for hf to be the difference between the two energy levels

Question 14

Absorption

Answer 14

When moving to higher energy, electron will emit color while absorbing photon.

Question 15

Fluorescence

Answer 15

When moving to lower energy, electron emits fluorescence while emitting photon