chemistry that i don't understand

what does the quantum mechanical model of electrons within an atom say

we cannot pinpoint where an electron is, but we can get the probability of where the electron is

sublevels -

correspond to the different areas an electron can be located in an electron

s sublevel shape

spherical

p sublevel

dumbbell

d sublevel

clover

f sublevel

double clover

type of sublevel - energy level 1

1s

type of sublevel - energy level 2

2s, 2p

type of sublevel - energy level 3

3s, 3p, 3d

type of sublevel - energy level 4

4s, 4p, 4d, 4f

type of sublevel - energy level 5

5s, 5p, 5d, 5f, (5g)

how many electrons can an atomic orbital hold

2 electrons

sublevel s

1 atomic orbital, max # of 2 electrons in sublevel

sublevel p

3 atomic orbitals, max # of 6 electrons in sublevel

sublevel d

5 atomic orbitals, max # of 10 electrons in sublevel

sublevel f

7 atomic orbitals, max # of 14 electrons in sublevel

sublevel g

9 atomic orbitals, max # of 18 electrons in sublevel

what are orbitals for a particular sublevel similar in?

shape, size, and orientation

\# of electrons in energy level 1

s, 2

\# of electrons in energy level 2

s&p, 2+6 = 8

\# of electrons in energy level 3

s, p, & d, 2+6+10 = 18

\# of electrons in energy level 4

s, p, d, & f, 2+6+10+14 = 32

rank of energy in an energy level

s

electrons prefer to occupy what?

orbitals that require the least amount of energy

how do electrons fill energy levels?

1st energy level, then 2nd energy level, then 3rd, etc…

an energy level is filled…

s, p, d, and then f

neutral atom:

p + = e- = atomic number

aufbau principle

electrons enter sublevels with the lowest energy first

for atoms with more than 18 electrons, sublevels are filled…

out of order, but the lowest energy sublevels are still filled first

increasing energy order

1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f, 6d, 7p

orbital notation…

uses circles to represent atomic orbitals with a label underneath to indicate sublevel and energy level

pauli principle

atomic orbitals can hold only 2 electrons at most, and they must have opposite spins

hund’s rule

in a sublevel with more than 1 orbital, put 1 electron into each orbital before putting 2e- into any one orbital

if an element is neutral…

\#e- = # of p+ = atomic #

how to write noble gas abbreviations

pick the closest noble gas to the element you are writing the configuration for that comes before that element

if two atoms have the same number of electrons, what are they?

isoelectronic

what element is O-2 isoelectronic with?

neon

valence electrons

electrons located in the outermost energy level

how do you count the number of valence electrons in the electron configuration?

look at the highest numbered energy level in the entire configuration, then add the electrons together

quantum numbers are used to…

describe the description of electrons in atoms

principle quantum number

n

angular momentum quantum number

l

magnetic quantum number

ml

electron spin quantum number

ms

the principle quantum number is described as…

the average distance of electrons to the nucleus. the larger the value, the further from the nucleus

angular momentum quantum number

shape of the orbitals. depends on n (0…n-1)

sublevel s

l = 0

sublevel p

l = 1

sublevel d

l = 2

sublevel f

l = 3

sublevel g

l = 4

magnetic quantum number

orientation of the orbital in 3D space. -l, 0, l

electron spin quantum number

electrons spin in 2 directions only. always valued at +1/2 or -1/2. +1/2 corresponds to the up spin of the electron, -1/2 corresponds to the down spin of the electron.