Exam 2

Question 1

principle quantum number

Answer 1

n = energy level of electron/orbital
positive integer

Question 2

angular momentum quantum number

Answer 2

l = shape of orbital
l = 0, 1, 2, …, n-1

Question 3

magnetic quantum number

Answer 3

mₗ = orbital orientation
mₗ = -l, …, 0, …, l

Question 4

spin quantum number

Answer 4

mₛ = spin of specific electron
mₛ = ±1/2

Question 5

letter names associated with l values
l = 0, 1, 2, 3, 4

Answer 5

l = s, p, d, f, g

Question 6

sketch orbital:
n=1
l=0

Answer 6

1s
0 nodes - nucleus doesn’t count
sphere

Question 7

sketch orbital:
n=2
l=0

Answer 7

2s
1 node - radial
hollow sphere

Question 8

sketch orbital:
n=2
l=1

Answer 8

2p
1 node - planar
dumbbell shape

Question 9

sketch orbital:
n=3
l=1

Answer 9

3p
2 nodes - 1 planar, 1 radial
dumbbell with 2 hats

Question 10

sketch orbital:
n=3
l=2

Answer 10

3d
2 nodes - planar
4 leaf clover or dumbbell with donut

Question 11

sketch orbital:
n=4
l=2

Answer 11

4d
3 nodes - 2 planar, 1 radial
4 leaf clover or dumbbell with 4 hats

Question 12

Hund’s Rule

Answer 12

Electrons should be placed evenly across degenerate orbitals before doubling up.

Question 13

Pauli’s Exclusion Principle

Answer 13

Every electron within an atom has a unique identity, as determined by its n, l, mₗ, and mₛ values.

Question 14

Aufbau Principle

Answer 14

When determining which electrons are in which orbitals, start from the lowest energy possibilities (orbitals).

Question 15

paramagnetic

Answer 15

there are unpaired electrons in the atom
net spin non-zero
affected by magnetic fields

Question 16

diamagnetic

Answer 16

all electrons are paired within the atom
net spin = 0

Question 17

atomic radius
(definition and periodic trends)

Answer 17

half of the distance between 2 bonded of an element
decreases across periods
increases down groups

Question 18

effective nuclear charge
(definition and periodic trends)

Answer 18

strength of the pull of the nucleus on electrons
increases across periods
decreases down groups

Question 19

ionization energy
(definition, periodic trends, and first vs. second ionization energy)

Answer 19

the energy required to move a valence electron
increases across periods
decreases down groups
first vs. second….

Question 20

ionic bonds nomenclature
e.g. NaCl
e.g. MgSO₄
e.g. FeCl₃

Answer 20

• metal (cation), then nonmetal (anion)
• cation element name + anion with “-ide” ending
• add roman numeral after cation if needed
  e.g. sodium chloride
  e.g. magnesium sulfate
  e.g. iron (III) chloride

Question 21

cation nomenclature
e.g. Al⁺
e.g. Fe³⁺

Answer 21

add “ion”
add roman numeral after element name if transition metal
e.g. aluminum ion
e.g. iron (III) ion

Question 22

monoatomic anion nomenclature
e.g. Cl⁻
e.g. O²⁻

Answer 22

add suffix -ide
e.g. chloride
e.g. oxide

Question 23

molecular compound nomenclature PREFIXES
1-10

Answer 23

1 = mono-
2 = di-
3 = tri-
4 = tetra-
5 = penta-
6 = hexa-
7 = hepta-
8 = octa-
9 = nona-
10 = deca-

Question 24

molecular compound nomenclature
e.g N₂O
e.g. ICl₃

Answer 24

• less electronegative element first
• add prefixes except for mono- on first element
• add “-ide” suffix to last element
  e.g. dinitrogen monoxide
  e.g. iodine trichloride

Question 25

electronegativity (definition, periodic trends, polarity of molecular compounds)

Answer 25

the ability of an atom to attract bonded electrons to itself increases across periods decreases down groups polar bonds occur when there is an electronegativity difference -- polar compounds exist when vectors don't cancel

Question 26

Formal charge (in a Lewis structure)

Answer 26

Calculate formal charge by subtracting the number of valence electrons around it in a compound from its atomic number - includes all lone pair electrons and half of all bonded electrons Prioritize lowest formal charges on each atom and opposite charges next to each other

Question 27

Violations of octet rule (Lewis structures)

Answer 27

- odd number of valence electrons --> free radical - incomplete octet --> usually caused by formal charge - expanded octet (period 3 or below) --> more electrons on central atom

Question 28

VSEPR electron domain geometries and angles for 2-6 domains

Answer 28

2 domains = linear (180°) 3 domains = trigonal planar (120°) 4 domains = tetrahedral (109.5°) 5 domains = trigonal bipyramidal (120° and 90°) 6 domains = octahedral (90°)

Question 29

2 electron domains: molecular geometries

Answer 29

2 bonding = linear

Question 30

3 electron domains: molecular geometries

Answer 30

2 bonding = bent (<120°) 3 bonding = trigonal planar (120°)

Question 31

4 electron domains: molecular geometries

Answer 31

2 bonding = bent (<<109.5°) 3 bonding = trigonal pyramidal (<109.5°) 4 bonding = tetrahedral (109.5°)

Question 32

5 electron domains: molecular geometries + bond positions

Answer 32

2 bonding (axial positions) = linear (180°) 3 bonding (axial + one equatorial) = T-shaped (90°) 4 bonding (axial + two equatorial) = seesaw (90° and <120°) 5 bonding = trigonal bipyramidal (90° and 120°)

Question 33

6 electron domains: molecular geometries (start at 4 bonding)

Answer 33

4 bonding = square planar (90°) 5 bonding = square pyramidal (<90°) 6 bonding = octahedral (90°)

Question 34

valence bond theory (2 types of bonds)

Answer 34

sigma (σ) bonds: head-to-head overlap --> single bonds pi (π) bonds: side-to-side overlap --> double bonds

Question 35

valence bond theory (significance of single, double, and triple bonds)

Answer 35

single bond = 1 σ bond double bond = 1 σ bond and 1 π bond triple bond = 1 σ bond and 2 π bonds