Chapter 5 - Electrons in Atoms Flashcards
quantum
the amount of energy required to move an electron from one energy level to another energy level
energy levels
the fixed energies an electron can have
quantum mechanical model
the modern description of the electrons in atoms that comes from the mathematical solutions to the Schrodinger equation
atomic orbital
a region of space in which there is a high probability of finding an electron
electron configurations
the ways in which electrons are arranged in various orbitals around the nuclei of atoms
aufbau principle
electrons occupy the orbitals of lowest energy first
Pauli exclusion principle
atomic orbital may describe at most two electrons
to occupy the same orbital, they must have opposite spins
Hund’s rule
electrons occupy the orbitals of the same energy in a way that makes the number of electrons with the same spin direction as large as possible
amplitude
the wave’s height from zero to crest
wavelength
the distance between the crests
symbol for wavelength
lambda
upside down y
frequency
the number of wave cycles to pass a given point per unit of time
symbol for frequency
v
unit for frequency
s^-1 or hertz
electromagnetic radiation
radio waves, microwaves, infrared, visible light, ultra violet, X-rays, gamma rays
spectrum
wavelengths of visible light that are separated when sunlight passes through a prism
atomic emission spectrum
the frequencies of light emitted by an element that separate into discrete lines
ground state
an electron has its lowest possible energy
photons
light quanta
Heisenberg uncertainty principle
it is impossible to know exactly both the velocity and the position of a particle at the same time
what did Democritus say about the atom
indivisible and indestructible
Dalton
solid sphere:
all elements composed of tiny indivisible particles
atoms are unique to that element
atoms of different elements can physically mix or chemically combine in simple whole number ratios to form compounds
chemical reactions occur when atoms are separated, joined, or rearranged, but they will not change elements
Thomson
plum pudding model - electrons
Rutherford
nucleus
positive dense center with electrons buzzing around
Bohr
electrons go in circular orbits
Schrodinger
quantum mechanical model - electron cloud
How many sublevels are in n=1
1
What type of orbitals are possible in n=1
s
max # of electrons in s
2
max. number of electrons in n=1
2
how many sublevels in n=2
2
type of orbitals in n=2
s
p
max number of electrons in p
6
max number of electrons in n=2
8
number of sublevels in n=3
3
types of orbitals in n=3
s
p
d
max number of electrons in d
10
max number of electrons in n=3
18
number of sublevels in n=4
4
orbitals in n=4
s
p
d
f
max number of electrons in f
14
max number of electrons in n=4
32
atomic orbitals in order
1s 2s 2p 3s 3p 4s 3d 4p 5s 4d 5p 6s 4f 5d 6p 7s 5f 6d 7p
3d^1 name the parts
3 - energy level/principal energy level
d - orbital/sublevel
1 - number of electrons
what happens when an atom absorbs energy
it goes from the stable ground state to the unstable excited state
what happens when an electron moves to a lower energy level
energy is released as light
What could Rutherford’s model not do?
explain the chemical properties of elements
what does the quantum mechanical model propose
electrons move only in specific circular paths, or orbits, around the nucleus
what does each sublevel of a principal energy level correspond to?
an orbital shape describing where the electron is likely to be found
what tell you how to find the electron configurations of atoms
aufbau principle
Pauli exclusion principle
Hund’s rule
why do some electron configurations differ from those assigned using the aufbau principle?
excited unstable ones that are not all filled
how are wavelength and frequency of light related
they are inversely proportional
the light emitted by an electron moving from a higher level to a lower level has a frequency ______ to the energy change of the electron
directly proportional
the difference between classical mechanics and quantum mechanics
classical mechanics adequately describes the motions of bodies much larger than atoms
quantum mechanics describes the motions of subatomic particles and atoms as waves
