Chapter 10 Chemical Bonding I: The Lewis Model

Question 1

what does the lewis model emphasize?

Answer 1

valence electrons

Question 2

Using Lewis model, we can draw chemical structures, called what?

Answer 2

Lewis structures
or
Electron dot structure

Question 3

what does the Lewis structure allow us to predict?

Answer 3

molecular stability
shape
size
polarity

Question 4

Chemical bonds form because they what between the charged particles that compose atoms.

Answer 4

lower the potential energy

Question 5

when does a chemical bond form?

Answer 5

when the potential energy of the bonded atoms is less than the potential energy of the separate atoms.

Question 6

When a metal atom loses electrons it becomes a WHAT?

Answer 6

Cation

Question 7

When a nonmetal atom gains electrons it becomes an what

Answer 7

anion

Question 8

what have high electron affinities?

Answer 8

nonmetals

Question 9

what makes it advantageous to add electrons to atoms

Answer 9

high electron affinities

Question 10

The oppositely charged ions are then attracted to each other, resulting in an

Answer 10

ionic bond

Question 11

have a high ionization energy

Answer 11

nonmetals

Question 12

when is the potential energy lowest?

Answer 12

when the electrons are between the nuclei

Question 13

The simplest theory of metallic bonding

Answer 13

metal atoms releasing their valence electrons to be shared as a pool by all

Question 14

where does metallic bonding result from?

Answer 14

attraction of the cations for the delocalized electrons.

Question 15

involves the transfer or sharing of valence electrons between two or more atoms.

Answer 15

chemical bonding

Question 16

are most important in bonding.

Answer 16

valence electrons

Question 17

indicates the number of valence electrons for main group elements.

Answer 17

column number on the periodic table

Question 18

how many electrons do transition elements have?

Answer 18

2

Question 19

how to represent valence electrons of main group electrons in the lewis structure?

Answer 19

dots surrounding the symbol for the element.

Question 20

We use the what to represent nucleus and inner electrons.

Answer 20

symbol of the element

Question 21

When atoms bond, they tend to gain, lose, or share electrons to result in eight valence electrons

Answer 21

Octet Rule `

Question 22

exceptions to octet rule

Answer 22

H
Li
Be
B

Question 23

having two valence electrons

Answer 23

a duet

Question 24

is the arrangement of cations and anions in a crystalline structure

Answer 24

crystal lattice

Question 25

long-range repeating order of the ions).

Answer 25

crystalline

Question 26

what is a crystal lattice held by?

Answer 26

the electrostatic attraction of the cations for all the surrounding anions.

Question 27

The extra stability that accompanies the formation of the crystal lattice is measured as the what?

Answer 27

lattice energy

Question 28

the energy released when the solid crystal forms from separate ions in the gas state.

Answer 28

lattice energy

Question 29

what does lattice energy depend directly on

Answer 29

size of charges

Question 30

what does lattice energy depend indirectly on

Answer 30

distance between ions

Question 31

is a hypothetical series of reactions that represents the formation of an ionic compound from its constituent elements.

Answer 31

Born-Haber Cycle

Question 32

The force of attraction between oppositely charged particles is directly proportional to what?

Answer 32

the product of the charges

Question 33

Larger charge the what the attraction

Answer 33

stronger

Question 34

the strong the attraction the what the Lattice energy

Answer 34

more

Question 35

all ionic compounds are what at room temp?

Answer 35

SOLID

Question 36

what kind of attraction is nondirectional

Answer 36

electrostatic attraction

Question 37

predicts ionic compounds should have high melting points and boiling points because breaking down the crystal should require a lot of energy.

Answer 37

Lewis theory

Question 38

the stronger the attraction, the what the melting point?

Answer 38

the higher

Question 39

is measured by rubbing two materials together and seeing which “streaks” or cuts the other.

Answer 39

hardness

Question 40

The harder material is the one that what?

Answer 40

cuts or doesn't streak

Question 41

To conduct electricity, a material must have what?

Answer 41

charged particles that are able to flow through the material.

Question 42

Lewis theory predicts that ionic solids should not conduct what?

Answer 42

electricity

Question 43

what should conduct electricity

Answer 43

liquid ionic compound and ionic compound dissolved in water

Question 44

The sharing of valence electrons is called

Answer 44

covalent bonding

Question 45

Electrons that are shared by atoms are called

Answer 45

bonding pairs

Question 46

Electrons that are not shared by atoms but belong to a particular atom are called

Answer 46

lone pairs or nonbonding pairs

Question 47

When two atoms share one pair of electrons, it is called a

Answer 47

single covalent bond

Question 48

When two atoms share two pairs of electrons the result is called a

Answer 48

double covalent bond

Question 49

When two atoms share three pairs of electrons the result is called a

Answer 49

triple covalent bond.

Question 50

Lewis theory of covalent bonding implies that the attractions between atoms are

Answer 50

directional

Question 51

Lewis theory predicts covalently bonded compounds will be found as what?

Answer 51

individual molecules

Question 52

Lewis theory predicts that the melting and boiling points of molecular compounds should be

Answer 52

low

Question 53

what bonds are strong and what attraction is weak

Answer 53

covalent attractions

Question 54

Lewis theory predicts that the hardness and brittleness of molecular compounds should vary depending on the

Answer 54

strength of intermolecular attractive forces.

Question 55

most of the molecular solids are what?

Answer 55

soft and waxy

Question 56

should the molecular solids conduct electricity?

Answer 56

no

Question 57

should the molecular liquids conduct electricity?

Answer 57

no

Question 58

what conducts electricity when dissolved in water?

Answer 58

Molecular acids

Question 59

Lewis theory predicts that the more electrons two atoms share, the what the bond should be.

Answer 59

stronger and shorter

Question 60

is measured by how much energy must be added to break the bond.

Answer 60

bond strength

Question 61

is determined by measuring the distance between the nuclei of bonded atoms

Answer 61

bond length

Question 62

Covalent bonding between different types of atoms results in

Answer 62

unequal sharing of electrons.

Question 63

unequal sharing of electrons.

Answer 63

polar covalent bond bond polarity

Question 64

The end with the larger electron density gets a what?

Answer 64

a partial negative

Question 65

The end that is electron deficient gets a

Answer 65

a partical positive charge

Question 66

The charged ends of the molecule represent a

Answer 66

dipole

Question 67

is a measure of bond polarity.

Answer 67

dipole moment

Question 68

is a material with a + and − end.

Answer 68

dipole

Question 69

Generally, the more electrons two atoms share and the larger the atoms, the what the dipole moment.

Answer 69

larger

Question 70

The ability of an atom to attract bonding electrons to itself is called

Answer 70

electronegativity

Question 71

is the most electronegative element.

Answer 71

fluorine

Question 72

is the least electronegative element.

Answer 72

francium

Question 73

are not assigned values.

Answer 73

noble gas atoms

Question 74

The larger the difference in electronegativity, the what the bond.

Answer 74

more polar

Question 75

If the difference in electronegativity between bonded atoms is what the bond is pure covalent.

Answer 75

0

Question 76

If the difference in electronegativity between bonded atoms is what the bond is nonpolar covalent

Answer 76

0.1 to 0.4

Question 77

If the difference in electronegativity between bonded atoms is what the bond is polar covalent

Answer 77

0.5 to 1.9

Question 78

If the difference in electronegativity between bonded atoms is what the bond is ionic

Answer 78

larger than or equal to 2.0

Question 79

is the percentage of a bond’s measured dipole moment compared to what it would be if the electrons were completely transferred.

Answer 79

percent ionic character

Question 80

The percent ionic character indicates the degree to which the electron is what?

Answer 80

transferred

Question 81

Elements with empty d orbitals can have more than eight electrons.

Answer 81

expanded octets

Question 82

Delocalization of charge helps to what?

Answer 82

stabilize the molecule

Question 83

When there is more than one Lewis structure for a molecule that differ only in the position of the electrons, they are called

Answer 83

resonance structures

Question 84

The actual molecule is a combination of the resonance forms a what?

Answer 84

resonance hybrid

Question 85

is a fictitious charge assigned to each atom in a Lewis structure that helps us to distinguish among competing Lewis structures.

Answer 85

formal charge

Question 86

most stable structures have what?

Answer 86

– Fewer formal charges. – Smaller formal charges. – Negative formal charges on the more electronegative atom.

Question 87

Chemical reactions involve breaking bonds in reactant molecules and making new bonds to create the products.

Answer 87

bond energies

Question 88

The amount of energy it takes to break one mole of a bond in a compound is called the

Answer 88

bond energy

Question 89

each atom gets 1⁄2 bonding electrons

Answer 89

Homolytic Cleavage

Question 90

electrons are unequally divided

Answer 90

Heterolytic Cleavage

Question 91

actual bond energy depends on what?

Answer 91

the surrounding atoms and other factors.

Question 92

The distance between the nuclei of bonded atoms is called the

Answer 92

bond length

Question 93

involves the metal atoms releasing their valence electrons to be shared by all atoms/ions in the metal.

Answer 93

The simplest theory of metallic bonding

Question 94

As temperature increases, the electrical conductivity of metals

Answer 94

decreases