EXAM 2: 06 Bonding

Question 1

What is the octet rule

Answer 1

In forming bonds, many main group elements gain, lose or share electrons to achieve a stable electron configuration, characterized by 8 valence electrons

Question 2

What is ionic bonding

Answer 2

Formed by ions of opposite charges
Found between atoms from opposite ends of the periodic table
Metals + nonmetals
Electrons are transferred

Question 3

Metals characteristics

Answer 3

Low ionization energy (can easily lose electrons), forms cations with noble gas configurations

Question 4

Nonmetal characteristics

Answer 4

Negative electron affinities (can easily gain electrons), forms anions

Question 5

What is metallic bonding

Answer 5

There are too few electrons to satisfy the octet rule, so valence electrons are shared among all metal atoms
The nuclei and core electrons are immersed in an electron sea composed of all valence electrons

Question 6

What is covalent bonding

Answer 6

Based on the sharing of electron pairs among directly bonded atoms
Forms when nonmetals share electrons
The number of desired covalent bonds must match the number of unpaired electrons in the Lewis structure

Question 7

Characteristics of metals

Answer 7

Good conductors of heat and electricity
Malleability and ductility

Question 8

Is the formation of ions of opposite charges from neutral atoms in the gas phase energetically favorable or unfavorable?

Answer 8

Energetically unfavorable

Question 9

What is atomization

Answer 9

To reduce or separate into atoms

Question 10

What is lattice energy

Answer 10

The amount of energy (enthalpy) required to convert a mole of ionic solid to its constituent ions in the gas phase
- measure the strength of ionic bonding

Question 11

What is a lattice

Answer 11

A 3d array of cations and anions in crystalline solids

Question 12

What is the trend for determining lattice energy

Answer 12

Increasing size = decreasing lattice energy
Increasing charge = increasing lattice energy

Question 13

Are there any direct bonds between ions?

Answer 13

No, just electrostatic attractions

Question 14

_____ melting point is associated with _______ lattice energy

Answer 14

High, high

Question 15

What are 2 rules for bonding

Answer 15

1. Only valence electrons are used in bonding
2. Atoms will gain, lose or share electrons to reach a noble gas configuration (filled shell)

Question 16

What is NH4+ called

Answer 16

Ammonium

Question 17

What is H3O+ called

Answer 17

Hydronium

Question 18

What is HO- called

Answer 18

Hydroxide

Question 19

What is O2- called

Answer 19

Peroxide

Question 20

What is CH3COO- called

Answer 20

Acetate

Question 21

What is C2O42- called

Answer 21

Oxalate

Question 22

What is CN- called

Answer 22

Cyanide

Question 23

What is SCN- called

Answer 23

Thiocyanate

Question 24

What is N3- called

Answer 24

Azide

Question 25

What is ClO- called

Answer 25

Hypochlorite

Question 26

What is ClO2- called

Answer 26

Chlorite

Question 27

What is ClO3- called

Answer 27

Chlorate

Question 28

What is ClO4- called

Answer 28

Perchlorate

Question 29

What is SO32- called

Answer 29

Sulfite

Question 30

What is SO42- called

Answer 30

Sulfate

Question 31

What is NO2- called

Answer 31

Nitrate

Question 32

What is NO3- called

Answer 32

Nitrate

Question 33

What is H2PO4- called

Answer 33

Dihydrogen phosphate

Question 34

What is HPO42- called

Answer 34

Hydrogen phosphate

Question 35

What is PO43- called

Answer 35

Phosphate

Question 36

What is HCO3- called

Answer 36

Hydrogen carbonate

Question 37

What is CO32- called

Answer 37

Carbonate

Question 38

What is MNO4- called

Answer 38

Permanganate

Question 39

What is CrO42- called

Answer 39

Chromate

Question 40

What is Cr2O72- called

Answer 40

Dichromate

Question 41

Characteristics of ionic compounds

Answer 41

High melting points, hard, brittle

Question 42

Increased repulsion = _______ energy

Answer 42

Increased

Question 43

What do Lewis structures illustrate

Answer 43

The apportionment of bonding and nonbonding electron pairs to atoms in molecules

Question 44

What are multiple bonds

Answer 44

A chemical bond in which two atoms share two or more pairs of electrons

Question 45

What is bond order

Answer 45

The number of electron pairs shared

Question 46

What do bond lengths depend on

Answer 46

Atomic bonding radii and bonding

Question 47

What is the relationship between bond order and bond length

Answer 47

The higher the bond order the shorter the bond

Question 48

What is the strength of a covalent bond defined by

Answer 48

The energy needed to break that exact bond while leaving other parts of the molecule intact - bond dissociation energy

Question 49

What is the relationship between strength of bond and bond dissociation energy

Answer 49

Stronger the bond, higher the BDE

Question 50

What is there relationship between bond length, bond order, bond strength and intermolecular forces

Answer 50

The shorter the bond length, and the higher the bond order, the stronger the bond is holding the atoms together within the molecule, and the weaker the intermolecular forces

Question 51

What is a polyatomic atom

Answer 51

An electrically charged group of two or more atoms; a molecule that has lost or gained one or more electrons

Question 52

How are atoms in polyatomic ions held together

Answer 52

Covalent bonding

Question 53

What is salt

Answer 53

An ionic compound

Question 54

Salt characteristics

Answer 54

Brittle at room temp, high melting points

Question 55

What are covalent substances and their characteristics

Answer 55

Often found as gases or liquids at room temp and pressure - in solid state: soft and melt easily - low melting and boiling points