Unit 4 (Electron Configuration) Flashcards
What does the Quantum Mechanical model of electrons within an atom say?
What do electron configurations show?
What orbitals do electrons prefer to occupy?
We cannot pinpoint where an electron is, but we can get the probability of where the electron is
They show how electrons are distributed within an atom
They prefer to occupy the orbitals that require the least amount of energy.
Explain energy levels and sub levels
1. The principled names
2. Lowest and highest in energy description
3. what do electrons occupy within levels
n =1, 2, 3, 4 etc. The average distance from an electron to the nucelus
Lowest is in the inner ring. Highest is outer
They occupy sublevels
Explain sublevels
1. What are the 4 letters that represent them in order?
2. What are the 4 shapes for each sub level
s, p, d, f
s - circle (spherical) shape
p - dumbbell or infinty symbol shape
d - clover shape
f - double clover shape
Explain the TYPES of sublevels for each energy level 1 through 5
1 - 1s
2 - 2s 2p
3 - 3s 3p 3d
4 - 4s 4p 4d 4f
5 - 5s 5p 5d 5f
Explain atomic ORBITALS.
1. What are they
2. how many electrons can they hold
3. for particular sublevels explain are they similar and different.
Each sublevel is oriented differently in 3-D space, and each orientation is an atomic orbital
atomic orbitals can only hold 2 electrons
Orbitals for particular sublevels are similar in shape, but different in orientation and size
Explain the # of atomic orbitals in each sublevel s-g, and each energy level 1-4.
s 1 orbs : 2e
p 3 orbs : 6e
d 5 orbs : 10e
f 7 orbs : 14 e
g 9 orbs : 18 e
1 (s) 2e
2 (s) (p) 8e
3 (s) (p) (d) 18e
4 (s) (p) (d) (f) 32e
How do you write electron configurations? (for neutral atoms)
How does it change for atoms with more than 18 electrons?
energy level (sublevel letter) ^ # of electrons
Ex Lithium has 3e, so 1s^2 2s^1
Sublevels are filled out of order after 3p BUT the lowest energy sublevels are still filled first!
Explain orbital notation?
1. what does it use and represent?
2. What are the symbols
3. examples?
uses boxes to represent atomic orbitals with a label underneath to indicate sublevel and energy level
One Electron = arrow up or boxed arrow up
Two Electrons = 2 arrows up and down or boxed arrow up and down
(Aufbau Principle)
Pauli’s Exclusion Principle (show an example too)
Hund’s Rule
(electrons enter sublevels with the lowest energy first)
Atomic orbitals can hold only 2 electrons at most and they must have opposite spins
* Nitrogen 1s^2 up-down 2s^2 up-down 2p^3 up up up. Get it?? Has to be possible
in a sublevel with more than one orbital, put one electron into each orbital before putting 2e-into any one orbital. Connects with Paul’s Exlcusion Principle
How do you write noble gas abbrevations?
1. what even are they?
2. What do they include
3. Actually explain how
Elements located in group 18
Include: He Ne Ar Xe Kr Rn Og
Pick the closest noble gas to the element you are writing the configuration for that comes before that element (EX: K Potassium [Ar] 4s^1)
Explain electron Configurations for Ions
1. What do they lose or gain to get the same number as
2. If two atoms have the same number of electrons, what are they said to be (Give examples)
3. explain charge and how to find the atom with an electron configuration
many elements will lose or gain electrons to obtain the same number of electrons as a noble gas
They are said to be isoelectronic EX: O-2 is isoelectronic with Neon
Remember charge. 1s2 2s2 2p6, with a +2 charge is Magnesium +2. It had to have lost electrons.
Explain Valence Electrons
1. What are they?
2. How to count them in 2 steps
3. Examples
electrons located in the outermost energy level. (Responsible for bonding)
Look at the highest numbered energy level in the entire configuration. Then add the electrons together
1s2 2s2 2p6
8 highest coefficient is 2. There’s 8 on the outside
Equations for
1. The speed of light
2. Energy formula
(Include ALL units )
C = wl * v
E = hv
C - 3.00 * 10^8 m/s
wl - wavelength (upsidedown lambda) in m nm or cm. 1m = 10^9 nm
v - frequency in hz or s^-1
E - energy in joules
h - planck’s constant. 6.626 * 10^-34 J * s
