General Chemistry Review for Organic Chem-Chapter 2

Each energy level split into what?

split into sub levels of differing energy

splitting is caused by what?

caused by penetration and its effect on shielding

for a given n value...

a lower l value indicates a lower energy level

order of sub level energies?

s

electron configuration is indicate by a shorthand notation:

this is the "address" for ALL the electrons in a given atom or ion

Key concept for electron configuration:

all the superscripts add up to give the number of electrons for the atom

A condensed electron configuration has...

the element symbol of the previous noble gas in square brackets

for a vertical orbital diagram an arrow is used to what?

an arrow is used to represent an electron and its spin direction

up arrow=

ms +1/2

down arrow=

ms -1/2

orbital diagrams use what?

use of a box, circle, or line for each orbital

electrons are always placed in the...

lowest energy sub level available

exclusion principle:

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

Hund's rule:

orbitals of equal energy (same sub level) will fill up with unpaired electrons before they start to pair up

explanation of Hund's rule:

electrons in same orbital repel each other

why do we write the energy levels form left to right (instead of vertically)?

to save space on paper

partial orbital diagram?

shows only the highest energy (highest n value) sub levels being filled

elements in the same group of the periodic table have the same what?

have the same outer electron configuration

elements in the same group of the periodic table exhibit what?

exhibit similar chemical behavior

similar outer electron configuration correlate with what?

correlate with similar chemical behavior

outer electrons:

are those with the highest n value

inner electrons:

those in common with the previous noble gas and any completed transition series (fully filled d or f sub levels)

valence electrons:

this involved in forming compounds

for main group elements, the valence electrons...

are the same as outer electrons (highest n value)

radius ("atomic size") is...

half the distance between nuclei

for nonmetal elements...

there is no clear boundary between the atoms as there is in metals

size does not...

mean same as mass

atomic size increases...

as the principal quantum number n increases

as n increases,

the probability that the outer electrons will be further from the nucleus increases

atomic size decreases...

as the effective nuclear charge Zeff increases

as Zeff increases,

the outer electrons are pulled closer to the nucleus

for main group elements, atomic size increases...

down a group and decreases across a period

down a group:

n and Z increases and S increases a lot, so Zeff decreases

across a period:

Z increases and S does not increase sufficiently to keep up, so Zeff increases

for main group elements, size is...

inversely related to Zeff

atomic size is measured in what units?

Zeff=Z-S