chem chapter 7

Question 1

degeneracy (long def)

Answer 1

in atoms, electrons occupy different energy levels/orbits. If multiple energy levels have the same energy, they are degenerate.

Question 2

degenerate (short def)

Answer 2

In a single electron atom, subshells/orbits with the same quantum number are degenerate

Question 3

what makes non-degeneracy?

Answer 3

sublevels with the same principal energy level

Question 4

shielding

Answer 4

-electrons closer to the nucleus can shield electrons farther out from the nucleus causing them to to have a lower Zeff and have a higher energy

Question 5

relate shielding to penetration

Answer 5

the closer, more penetrating orbital, shields the further out orbitals from the nucleus

Question 6

penetration

Answer 6

orbitals with radial probability closer to the nucleus are more penetrated (they are closer to the nucleus)

Question 7

paramagnetic

Answer 7

in the orbital diagram/chart- there are unpaired electrons (they are drawn to magnets)

Question 8

diamagnetic

Answer 8

in electron chart/orbital diagram- paired electrons (slightly repel magnets)

Question 9

what is the order of assigning electrons to orbitals?

Answer 9

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

Question 10

pauli exclusion principle

Answer 10

no two electrons can have the same quantum numbers (n,l,ml,ms)
-only two electrons in the same orbital and they must have opposite spins

Question 11

aufbau principle

Answer 11

electrons fill lower energy orbitals first

Question 12

hunds rule

Answer 12

when multiple degenerate orbitals are available, electrons fill each singly with parallel spins before pairing
-orbitals with the same n and l values are degenerate in a multi-electron atom

Question 13

effective nuclear charge (Zeff)

Answer 13

-an atom with electrons closer to the nucleus will generally have a higher Zeff
-Zeff increases from left to right
-Zeff=atomic number - number of core electrons

Question 14

valence electrons

Answer 14

electrons in the outermost shell (highest principal quantum number)

Question 15

transition metal exceptions with filling behavior

Answer 15

groups 6B and 11B
-instead of having a full ns orbital and (n-1)d^4 or (n-1)d^9 they move one electron up to the (n-1)d orbital taken from the ns orbital
-Cr, Mo, Cu, Ag, Au

Question 16

excited state electron configurations

Answer 16

the electron will be missing from a lower energy level subshell and moved to a higher energy sublevel

Question 17

electron configurations of ions: cation

Answer 17

when an atom loses electrons (makes a cation), it loses the highest principle energy level first

Question 18

electron configuration of ions: anions

Answer 18

electrons fill to minimize their energy and anions will continue the same filling pattern as other atoms

Question 19

predicting ion charges: cation

Answer 19

look for which electrons will come off first: valence electrons

Question 20

predicting ion charges: anion

Answer 20

look for how many electrons are needed to reach an octet (8e-)

Question 21

ionization energy

Answer 21

-the amount of energy required to remove an electron from a neutral atom in the gas phase
-endothermic

Question 22

ionization energy trend and exceptions on the periodic table

Answer 22

it increases left to right and up
-exceptions:
switch groups 2 and 13 (13 has lower IE than expected)
switch groups 15 and 16 (16 has lower IE than expected)

Question 23

electron attachment enthalpy

Answer 23

the enthalpy change when a gaseous atom adds and electron forming a gaseous anion
this process is negative or exothermic

Question 24

electron affinity

Answer 24

the energy required to detach an electron to form an anion with a -1 charge
typically positive and is endothermic

Question 25

what is the periodic trend for electron attachment enthalpy and electron affinity?

Answer 25

it becomes more favorable (increases) from the left to the right and up the periodic table

Question 26

what are the exceptions for EA and EAE

Answer 26

-row 2 has a lower (less favorable) than row three
-noble gases are very unfavorable
-group 2 and 15 are less favorable than expected so groups 1 and 2 switch and groups 14 and 15 switch

Question 27

atomic radius

Answer 27

measure of the size of the atom

Question 28

atomic radius periodic trend

Answer 28

atomic radius increases from the right to the left and down the periodic table (opposite of what you would think)

Question 29

polarizability

Answer 29

tendency of an atom to become polarized
larger atoms have a higher polarizability because electrons are farther from the nucleus

Question 30

polarizability on the periodic table

Answer 30

it increases from the left to the right and down the periodic table
IMPORTANT: cations are smaller and anions are larger!

Question 31

electronegativity

Answer 31

measure of an atoms ability to attract electrons to itself

Question 32

electronegativity on the periodic table

Answer 32

EN increases from the left to the right and up the table
HOWEVER, noble gases are excluded!
fluorine is the most electronegative and francium is the lest electronegative