Chapter 5

Question 1

properties of molecular substances depend on the _____ of the molecule

Answer 1

structure

Question 2

The structure of a molecule includes many factors:
1. the skeletal arrangement of _____
2. the kind of _____ between the atoms
3. the ____ of the molecule
_____ theory predicts shapes of molecules

Answer 2

1. atoms
   2, bonding
2. shape
3. bonding

Question 3

Electron groups around the central atom will be most stable when they are as far apart as possible is the basis for ______ theory

Answer 3

VSEPR (valence shell electron pair repulsion)

Question 4

Because electrons are negatively charged, they should be most stable when they are _____ as much as possible

Answer 4

separated

Question 5

Geometric arrangement will allows us to predict the _____ and _____ _____ in the molecule

Answer 5

shape, bond angles

Question 6

The Lewis structure predicts the number of _____ _____ ____ around the central atom
Each ____ _____ of electrons constitutes one electron group on a central atom
Each _____ constitutes one electron group on a central atom, regardless of what kind it is
- Determined by the number of ____ around the central atom

Answer 6

valence electron pairs
lone pair
bond
atoms

Question 7

How do you find Steric Number (SN)?

Answer 7

SN = (number of atoms bonded to central atom) + (number of lone pairs on central atom)

Question 8

If a lone pair is attached to the _____ _____ in the molecule it affects the shape

Answer 8

central atom

Question 9

type of geometry

3D arrangements of electron pairs (bonds or lone pairs) around a central atom

Answer 9

electron-pair geometry

Question 10

type of geometry

3D arrangement of the atoms in a molecule

Answer 10

molecular geometry

Question 11

if there are no lone pairs (on central atom), the electron-pair geometry and molecular geometry are ____

Answer 11

the same

Question 12

electron-pair geometry and molecular geometry for a molecule with 2 SN and zero lone pairs
angle?

Answer 12

linear for both

180 degrees

Question 13

electron-pair geometry and molecular geometry for a molecule with 3 SN and zero lone pairs
angle?

Answer 13

trigonal planar for both

120 degrees

Question 14

electron-pair geometry and molecular geometry for a molecule with 3 SN and one lone pair
angle?

Answer 14

e.g. - trigonal planar
m.g. - bent
<120 degrees

Question 15

electron-pair geometry and molecular geometry for a molecule with 4 SN and zero lone pairs
angle?

Answer 15

tetrahedral for both

109.5 degrees

Question 16

electron-pair geometry and molecular geometry for a molecule with 4 SN and one lone pair
angle?

Answer 16

e.g. tetrahedral
m.g. trigonal pyramidal
<109.5 degrees

Question 17

electron-pair geometry and molecular geometry for a molecule with 4 SN and two lone pairs
angle?

Answer 17

e.g. tetrahedral
m.g. bent
<109.5 degrees

Question 18

electron-pair geometry and molecular geometry for a molecule with 5 SN and zero lone pairs
angle?

Answer 18

trigonal bipyramidal for both

90 degrees; 120 degrees

Question 19

electron-pair geometry and molecular geometry for a molecule with 5 SN and one lone pair
angle?

Answer 19

e.g. trigonal bipyramidal
m.g. seesaw
<90 degrees; <120 degrees

Question 20

electron-pair geometry and molecular geometry for a molecule with 5 SN and two lone pairs
angle?

Answer 20

e.g. trigonal bipyramidal
m.g. T-shaped
<90 degrees

Question 21

electron-pair geometry and molecular geometry for a molecule with 5 SN and three lone pairs
angle?

Answer 21

e.g. trigonal bipyramidal
m.g. linear
180 degrees

Question 22

electron-pair geometry and molecular geometry for a molecule with 6 SN and zero lone pairs
angle?

Answer 22

octahedral for both

90 degrees

Question 23

electron-pair geometry and molecular geometry for a molecule with 6 SN and one lone pair
angle?

Answer 23

e.g. octahedral
m.g. square pyramidal
< 90 degrees

Question 24

electron-pair geometry and molecular geometry for a molecule with 6 SN and two lone pairs
angle?

Answer 24

e.g. octahedral
m.g. square planar
90 degrees

Question 25

When the electron groups are attached to atoms of different size or when bonding to one atom is different than the bonding to another, this will affect the ______ geometry around the central atom

Answer 25

molecular

Question 26

lone pairs also affect the _____ geometry

Answer 26

molecular

Question 27

Lone pair groups: occupy ______ on the central atom but are not seen as points on the molecular geometry take up more space on the central atom because their electron _____ is exclusively on the central atom, rather than shared like bonding electron groups this affects the bond _____, making the bond-pair angles smaller than expected

Answer 27

space density angles

Question 28

For a molecule to be polar, it must have the following 1. 2.

Answer 28

1. polar bonds | 2. an unsymmetrical shape

Question 29

polarity affects the _______ forces of attraction | example

Answer 29

intermolecular | boiling point, solubilities

Question 30

Lone pairs affect molecular _____, a strong pull in their direction

Answer 30

polarity

Question 31

Problems with Lewis Bonding Theory does not give good ______ predictions usually cannot be used to ger the actual bond _____ uses multiple structures to represent ______ electrons

Answer 31

numerical angle delocalized

Question 32

When atoms come together to form bonds, the electrons of one atom are _____ to the protons of the other atom while the electrons of each atom ____ each other

Answer 32

attracted; repel

Question 33

the electrons in overlapping atomic orbitals are attracted to the nuclei of both bonded atoms, increasing stability is what theory?

Answer 33

valence bond theory

Question 34

bond direct, head-on overlap of orbitals (one area of overlap) covalent bond resulting from the end-to-end overlap of atomic orbitals along the internuclear axis

Answer 34

sigma bond

Question 35

bond | side-by-side overlap of orbitals (Two areas of overlap)

Answer 35

pi bonds

Question 36

How many sigma/pi bonds are in a single bond?

Answer 36

1 sigma bond

Question 37

How many sigma/pi bonds are in a double bond?

Answer 37

1 sigma; 1 pi

Question 38

How many sigma/pi bonds are in a triple bond?

Answer 38

1 sigma; 2 pi

Question 39

If the SN is 2 what is the # of hybrid orbitals and what is the hybrid orbital?

Answer 39

2; sp

Question 40

If the SN is 3 what is the # of hybrid orbitals and what is the hybrid orbital?

Answer 40

3; sp^2

Question 41

If the SN is 4 what is the # of hybrid orbitals and what is the hybrid orbital?

Answer 41

4; sp^4

Question 42

If the SN is 5 what is the # of hybrid orbitals and what is the hybrid orbital?

Answer 42

5; sp^3d

Question 43

If the SN is 6 what is the # of hybrid orbitals and what is the hybrid orbital?

Answer 43

sp^3d^2

Question 44

A set of 4 hybrid orbitals with a tetrahedral orientation produced by mixing one s and three p orbitals

Answer 44

sp^3

Question 45

A set of 3 hybrid orbitals with trigonal planar orientation produced by mixing one s and two p orbitals The two lobes of the unhybridized p orbital lie above and below the plane of the triangle of

Answer 45

sp^2

Question 46

A set of 2 hybrid orbitals with linear orientation produced by mixing one s and one p orbital

Answer 46

sp

Question 47

atom with unpaired electrons

Answer 47

paramagnetic

Question 48

atom with all electrons paired

Answer 48

diamagnetic

Question 49

theory based on quantum mechanics that constructs molecular orbitals from wave functions

Answer 49

molecular orbital

Question 50

When the wave functions combine constructively, the resulting molecular orbital has ____ energy than the original atomic orbitals called a ______ ______ ______ and designated: sigma, most of the electron ______ between the nuclei

Answer 50

less bonding molecular orbital density

Question 51

When the wave functions combine destructively, the resulting molecular orbital has ____ energy than the original atomic orbital called an _____ _______ ______ and designated: sigma*, pi* ____ between nuclei

Answer 51

more antibonding molecular orbital nodes

Question 52

how do you find bond order?

Answer 52

(number of bonding electrons - number of antibonding electrons) / 2

Question 53

For 2p, you put 2p pi under sigma for which molecules?

Answer 53

Li2, Be2, B2, C2, and N2

Question 54

For, 2p you put 2p pi above sigma for which molecules?

Answer 54

O2, F2, Ne2