Chemistry Midterms

Electron Configuration

shorthand way of determining the probable location of the electrons of an atom

nl^#

nl^#

n - energy lvl where the electrons are found

l - subshell where the electrons are found

# - # of electrons found in the energy lvl/subshell

Aufbau principle

electrons are always placed in the lowest energy sublvl available

• the sublvls that are filled later w/ electrons have more energy lvls

• its okay if the remaining electrons don’t completely fill a sublvl

Pauli exclusion principle

each atomic orbital may contain a maximum of 2 electrons, which must have opposite spins

no 2 electrons in the same atom can have the same 4 quantum nos.

1s

has the lowest energy bcs its nearest to the nucleus

7p

highest (non-hypothetical) energy lvl bcs its the farthest from the nucleus

Hund’s rule

when orbitals of = energy are available, the lowest energy electron configuration has the maximum number of unpaired electrons w/ parallel spins

atomic orbitals of = energy are filled up singly 1st b4 being doubly occupied

finding the nth electron of an element

count using Hund’s rule and Aufbau principle

l - look at shape

ml - look at integer of the line

ms - look at orientation of the electron