Energy Levels in Atoms Flashcards
What is the n = 1 energy level?
The ground state, the lowest energy level an electron can be in
What does it mean if an electron is “excited”?
When the electron collides with another electron or absorbs a photon , it moves to a higher energy level
What is the formula for the transition between two energy levels?
ΔE = E₁ + E₂ = hf
What does ionisation mean?
When an electron has been removed from an atom
What is the ionisation energy?
The amount of energy needed to remove an electron from the ground state
How do fluorescent tubes work?
They contain mercury vapour across which a high voltage is applied. The voltages causes the mercury to become ionised causing free electrons in the tube. The free electrons collide with other electrons in the mercury atoms causing them to get excited, when the electrons return back to ground state some energy is released as photons. The inside of the tube is coated with phosphorus which absorbs the photons, exciting its electrons to much higher energy levels
How does line spectra provide evidence for discrete energy levels?
Electrons can only emit photons with energies equal to the difference between two energy levels. Since only certain energies are allowed, you only see the corresponding wavelengths
What happens if the electron colliding with another electron doesn’t have enough energy to cause excitation?
It’s deflected with no loss of kinetic energy