atomic structure Flashcards
(24 cards)
What phenomenon describes the dual nature of matter exhibiting both particle-like and wave-like behavior?
Wave-particle duality
What does the Heisenberg uncertainty principle state?
We cannot know both the position and speed of a particle with perfect accuracy
How is the location of an electron defined?
As a probability of finding the electron at a certain point or within a certain region
What is the most important outcome from the Schrödinger equation?
The wavefunction Ψ
What is true about the wavefunction Ψ in terms of physical measurement?
It is not related to anything physical and cannot be measured experimentally
If the electron is defined by the Schrödinger equation, what does Ψ represent?
The amplitude of that equation at a given value of (x,y,z)
What does Ψ squared (Ψ²) represent?
The probability of finding the electron at (x,y,z)
What do quantum numbers determine in quantum mechanics?
The viable electronic configuration and probability distribution
What does the Principal quantum number determine?
The size of the orbital and therefore the energy
What is the relationship between the Principal quantum number (n) and the distance of electrons from the nucleus?
Electrons in orbitals with n = 1 will be closer to the nucleus than those in orbitals with n = 2
What does the angular momentum number (l) describe?
The shape of the sublevel within an energy level
What are the possible values for the angular momentum number (l) based on the type of sublevel?
- For s: l=0
- For p: l=1
- For d: l=2
- For f: l=3
What is the constraint on the angular momentum number (l)?
l < n - 1
What does the magnetic quantum number (ml) describe?
The orbital within the sublevel
What is the range of values for the magnetic quantum number (ml)?
-l < ml < l
What does a negative value for R in radial wavefunctions indicate?
It indicates the phase of the wavefunction
The phase of the wavefunction is significant in quantum mechanics as it affects interference patterns.
What does RDF stand for in the context of electron probability?
RDF = probability of electron being at distance r × number of locations at distance r
RDF is used to calculate the likelihood of finding an electron at a specific distance from the nucleus.
What are nodes in the context of wavefunctions?
Nodes are distances from the nucleus with zero probability
Nodes indicate regions where the likelihood of finding an electron is zero.
What does the angular wavefunction depend on?
numbers
The angular wavefunction is dependent on l and ml only
Here, l is the azimuthal quantum number, and ml is the magnetic quantum number.
What are radial and angular nodes?
Radial nodes are distances from the nucleus with zero electron probability.
Angular nodes are distances from the nucleus with zero electron probability
Radial nodes occur at specific radii where the wavefunction equals zero.
What is the shielding effect?
electron shielding
electrons closer to the nucleus ) prevent the outer electrons from feeling the full nuclear charge that they would do in isolation; the outer electrons therefore experience a lower effective nuclear charge Zeff, and therefore have a higher energy than expected
Are electrons with a larger n higher or lower in energy?
Electrons in orbitals with larger n have a probability distribution further away from the nucleus; they experience less of the nuclear charge and are therefore less tightly bound – higher energy.
do orbital energies increase or decrease with atomic number?
Decrease. A higher nuclear charge means that the electrostatic attraction to the electroms increases.
What is the 4th quantum number and what principle reates to it?
The spin quantum number, with 2 values of +1/2 or -1/2. Relating to Aufbau principle.
> “To move from one element to the next, add one proton and some neutrons to the nucleus, and one electron to the orbital of lowest energy which is available”
