quantum model and electron configuration

Similarities in Quantum and Bohr

- energy of electrons are quantized (can only have certain values)
- electrons CAN move in between energy levels and sub levels by absorbing or releasing energy

Quantum Model

- position can be estimated with probability (cannot be known with certainty)
- there are sublevels and orbitals
- electrons move freely within these regions (orbitals)

Bohr Model

- electron’s position and momentum are known - given by the size of its “orbit” (energy level)
- energy levels only, no further divisions.

Brogile

developed an equation for determining the wavelength of any object

Heisenberg Uncertainty Principle

It is impossible to measure the exact position (x) and the exact momentum (p) of an electron simultaneously!

- the more we know about one variable, the less we know about the other variable
-> we sacrifice certainty in the electron’s position for certainty in it’s momentum (energy)

Schrodinger

developed a mathematical equation to describe the wavelike nature of electrons in an atoms
- solutions -> orbitals

(basically went from orbits to orbitals)

What does Schrodinger's equation do?

computes the probability of finding an electron (with a specific energy) in a certain region of space.

Difference between orbitals and orbits

orbit - a fixed path along which electrons revolve around the atom's nucleus

orbital - is an area used to calculate the probability of finding any electron

The space representing where an electron could be found is shown by ____

a fuzzy cloud like region

True or False? The cloud is more dense where the probability of finding the electron is high

true

name all the orbitals

s, p, d , f

shapes of orbitals

s -> spherical
p -> dumbbell
d -> clover
f -> complex

sizes of s-orbitals

n increases = size and most likely distance at which to find the electron increases

How many electrons does each orbital hold?

2

What is an orbital’s size and shape determined by?

the electron's energy

Total electrons in each sub level

s-sublevel = 2 electrons
p-sublevel = 6 electrons
d-sublevel = 10 electrons
f-sublevel = 14 electrons

Aufbau Principle

lower energy orbitals must be filled completely
before electrons can be distributed to higher energy
orbitals

EX:
4s^2 comes before 3d^10 because it's a lower energy orbital

Exceptions to Aufbau Principle

chromium
copper
they both promote a 4s electron to the 3d sublevel!

Hund's Rule

place one electron per orbital before pairing them
EX: when drawing electron configuration (boxes), you have to give each box one arrow before pairing it with another

Pauli's Exclusion Principle

each orbital can hold only TWO electrons and they
must have opposite spins
EX: the drawn electron configuration must have two arrows pointing in OPPOSITE directions

Electron Configuration of Kr (36)

1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10 4p^6