Ch 5: Electrons in Atoms/Electrons Flashcards
What could Rutherford’s atomic model not explain?
The chemical properties of elements.
What did Bohr propose about an electron?
It is found only in specific circular paths, or orbits, around the nucleus.
What did Bohr note that atoms emit?
Light of specific colors and wavelengths.
What did Bohr determine light came from?
Excited electrons when energy is lost.
Electrons could only have certain _________ energies.
quantized
What are these characteristics of:
- Atoms only emit a few energies of light.
- Energy can only have certain specific qualities.
- Energy levels are clearly defined values and are not flexible.
- If there were any random value, a continuous spectrum of light would be emitted.
Quantized energy
What was Bohr correct about? What was Bohr incorrect about?
Correct: energy levels.
Incorrect: the orbits.
The energy levels in an atom are not _______ ______. The higher energy levels are ______ ________.
equally spaced.
closer together.
Who developed the Quantum Mechanical Model?
Erwin Schrödinger.
What does the quantum mechanical model determine?
The allowed energies an electron can have and how likely it is to find the electron in various locations around the nucleus.
Electrons in atoms behave like _____.
waves.
Electrons: there is a fundamental ___________ about their behavior; cannot map path.
uncertainty
Electrons: waves are ___________, but we can assign a location based on ___________.
delocalized
probability.
Atomic orbitals: each energy sub level corresponds to an orbital of a different _____, which describes where the electron is likely to be _____.
shape
found.
Atomic orbitals: the region where there is a ___ ______ of finding an electron is called an _______.
90% chance
orbital.
Atomic orbitals: what are orbitals characterized by?
Energy levels and sub levels.
What three rules tell how to find the electron configuration of atoms?
- Aufbau principle
- Pauli exclusion principle
- Hund’s rule
Some actual electron configurations differ from those assigned using the aufbau principle because ____-______ sub levels are not as stable as ______ sub levels. They are more stable than other ______________.
half-filled
filled
configurations.
What are the 5 properties of waves?
- speed
- wavelength
- frequency
- energy
- hertz
The __________ and _________ of light are inversely proportional to each other.
wavelength
frequency
What type of waves does the electromagnetic spectrum include?
Radio waves, microwaves, infrared waves, visible light, ultraviolet waves, X-rays, and gamma rays.
What is the electromagnetic spectrum?
The full range of electromagnetic energy (waves of electric and magnetic fields, oscillating at right angles to each other).
What is the dual nature of light?
Light is made up of matter and waves.
When atoms absorb energy, electrons move into ____ energy levels.
These electrons lose the energy by emitting _____ when they return to lower energy levels.
high
light
According to the Aufbau principle, in the ______ _____, electrons have the lowest energy level possible.
ground state
Each energy level () has a certain number of sub levels (, _, _, _).
n
s, p, d, f
Each sub level has a certain number of orbitals (_, _, _, _).
1, 3, 5, 7
Two electrons can share an orbital only if they have ________ _____.
opposite spins
At the highest energy level, the electrons will ______ ___ to be ________ where possible. All ________ electrons will have the ____ spin.
spread out
unpaired
unpaired
same
A _______ of energy in the form of _____ is emitted when the electron drops back to a lower energy level. This single step is known as __________ __________.
quantum
light
electronic transition
The light emitted by an electron moving from a higher to a lower energy level has a _________ directly proportional to the ______ ______ of the electron.
frequency
energy change
Classical mechanics adequately describes the motions of bodies much ______ than atoms, while quantum mechanics describes motions of _________ _________ and _____ as waves.
larger
subatomic particles
atoms
Quantum mechanics is considered the _____ theory.
Classical mechanics is considered the _____ theory.
newer
older
Planck discovered _____ _______ (E=hf).
light photons
Einstein said: light has ____; it is ______ (E=mc^2).
mass
matter
DeBroglie said: As the mass _________, the __________ decreases. Electrons behave like _____.
increases
wavelength
waves.