Ch. 8 Quantum Mechanics And Periodic Trends Flashcards
The theory which allows us to determine the probability of finding an electron at a particular place in the Atom
Quantum mechanics
Modern atomic theory is referred to as
Quantum mechanics
It is impossible to know both the speed and location of an electron at the same time
Heisenberg uncertainty principle
Particles that are involved in light
Photons
What is the principal quantum number
Describes the main energy level of the electron in its distance from the nucleus
How do you calculate the principal quantum number
2n^2
What levels to the electrons occupy
The lowest energy levels which are the closest to the nucleus
Azimuthal quantum number
Describes the sub level the electron is in
List the sub levels in order from least energetic to most energetic
S
p
D
F
Azimuthal quantum number
Also describes the shape of the electron cloud
Region of space in which an electron of a particular energy might be found
Electron cloud
What does the S as azimuthal quantum number look like
Sphere
What does the P look like
Propeller
What does the d look like
Daisy
What does the f look like
Too funky to draw
The shape of the space where there is a high probability of finding electrons
Orbital
Magnetic quantum number (m)
Describes the orbitals orientation in space
Represents the number of ways in which you can position an electron cloud
The space occupied by a pair of electrons
Orbital
When placing electrons into orbitals within a sub level place them in orbitals one at a time before doubling up
Hund’s role of maximum multiplicity
Spin quantum number (s)
Represents the direction of the electron spin
Where does an electron spin and how
Electron spins on its axis clockwise and counterclockwise
No two electrons in the same atom can have the same set of four quantum numbers
Pauli exclusion principle
Having the same energy
Degenerate
Electrons will remain unpaired in a given orbital until orbitals of the same sublet will have at least one electron
Hund’s rule
What sublevels overlap
The 4s and 3d
Went to the overlaps become more frequent
As electrons are placed in n=5 and beyond
How are energy levels spaced
They are not equally spaced as you get further from the nucleus energy levels get closer together and overlap
A property that can be predicted based on an elements location on the periodic table
Periodic trend
The distance from the center of the nucleus to the edge of the electron cloud
Atomic radius
Why do scientists use a covalent radius or half the distance between the nuclei of two bonded Atoms
Because an electron clouds edge is difficult to define
What is an Angstrom
1×10 to the -10 m
What is the trend for atomic radius
Larger as you go down the column and smaller as you go to the right in the row
What is the atomic radius get larger as you go down the column
Because each step down adds an entirely new main energy level making the Atoms larger
What is the atomic radius get smaller as you go to the right in the row
Because each step right adds a proton and an electron yet the Atoms do not get larger because they are added to existing main energy levels the added electrons are not farther from the nucleus and the effective nuclear charge is greater
Attraction that pulls the electron cloud in
Effective nuclear charge
Pull that an electron feels from the nucleus
Effective nuclear charge
The larger the effective nuclear charge
The tighter the electron cloud gets pulled in
Why don’t we see the effective nuclear charge occur when going down the column
As more main energy levels are added to the Atoms the inner layers of electrons shield the outer electrons from the nucleus
The energy required to remove an electron from an Atom
Ionization energy
What is the relationship between ionization energy and atomic radius
Inversely proportional
Ionization energy is always
Endothermic
Energy is added to the atom to remove the electron
A measure of an atom’s desire for electrons in a chemical bond
Electronegativity
What element has the highest electronegativity in what is the value
Fluorine the value is 4
Which elements or electron dinners and have low electronegativities
Metals
Which elements are electronic accepter’s and have high electronegativities
Nonmetals
Best electron dinners and the largest
Metals
Best electron takers and are the smallest
Nonmetals
No electronegativities
Noble gases
All of the ions with the same electron configuration
Isoelectronic series
Goes from regular element to negative ion
Ion is bigger less effective nuclear charge
Goes from regular element to Positive ion
Ion is smaller
Why don’t elements change in an isoelectronic series
Because protons determine the element
Equations needed to calculate the energy involved in an electron transition
Delta E equals RH times the quantity one over ni squared -1 over nf squared
E equals HV
C equals V upside down y
Number of cycles that pass in a certain amount of time
Frequency
V
Frequency
Upside down y
Wavelength
