Inorganic Chemistry Test 1 Part 3 Of 5

Front 1

Define Arrhenius Acid

Back 1

Things that dissociate in aqueous solution to form hydrogen ions

Front 2

Define Arrhenius Base

Back 2

Things that dissociate in aqueous solution to form hydroxide ions

Front 3

Define Bronsted Acid

Back 3

A proton donor

Front 4

Define Bronsted Base

Back 4

A proton acceptor

Front 5

Define Lewis Acid

Back 5

A compound or ionic species that can accept an electron pair from a donor compound

Front 6

Define Lewis Base

Back 6

A compound or ionic species that can donate an electron pair to an acceptor compound

Front 7

Define Grotthuss mechanism

Back 7

A mechanism that describes the way protons rapidly move through water whereby protons tunnel from one water molecule to the next via hydrogen bonding.

Front 8

Given pH, how do you find pOH, [H⁺], and [OH⁻]

Back 8

pOH = 14- pH;

[H⁺] = 10^-pH;

[OH⁻] = 10^-(14-pH);

Front 9

Given concentrations of [H+] and [HX], how do you find Ka

Back 9

Ka = [H⁺] [X⁻]/ [HX]

Front 10

Given concentrations of [H+] and [HX], how do you find Kb

Back 10

Kb = [HB⁺] [X⁻]/ [B]

Front 11

Formula for Kw

Back 11

Kw = [H₃O⁺] [OH⁻]

Front 12

How are the strengths of a conjugate acid and base related

Back 12

Ka · Kb = Kw

Front 13

Formula for pKa from Ka (applies to pKb and pKw as well)

Back 13

pKa = -log(Ka)

Front 14

Relation of pKa, pKb, and pKw

Back 14

pKa + pKb = pKw

Front 15

Relation between Ka and strength of an acid

Back 15

A bigger Ka means a stronger acid

Front 16

Relation between Kb and strength of a base

Back 16

A bigger Kb means a stronger base

Front 17

Relationship between the strength of an acid/base and the strength of its conjugate acid/base

Back 17

The stronger the acid/base, the weaker its conjugate acid/base. They are inversely proportional

Front 18

Define leveling effect

Back 18

When acids are so strong that it is impossible to tell which one is stronger because they are stronger than the solvent's conjugate acid, the solvent is said to have a leveling effect on the acids. For example, water has a leveling effect because it brings all acids stronger than H₃O⁺ down to the level of H₃O⁺

Front 19

Define aqua acid

Back 19

An acid in which the acidic proton is on a water molecule coordinated to a central metal ion. For example, [Fe(OH₂)₆]³⁺

Front 20

Define hydroxoacid

Back 20

An acid in which the acidic proton is on a hydroxyl group without a neighboring oxo group (=O). An example is Te(OH)₆

Front 21

Define oxoacid

Back 21

An acid in which the acidic proton is on a hydroxyl group with an oxo group attached to the same atom. An example is sulfuric acid (H₂SO₄)

Front 22

How are aqua acids, hydroxoacids, and oxoacids related

Back 22

The three classes of acids can be regarded as successive stages in the deprotonation of an aqua acid

Front 23

Trends in the strength of aqua acids

Back 23

The strengths of aqua acids typically increase with increasing positive charge of the central metal ion and with decreasing ionic radius

Front 24

Strength of substituted oxoacids based on their substituents

Back 24

If the substituent is an electron withdrawing group, then it is a stronger acid. If the substituent is an electron releasing group, it is a weaker acid. The degree of strengthening or weakness depends on how good of a withdrawer or donator the group is

Front 25

Pauling's rules

Back 25

p = number of oxo groups, and q = number of hydroxyl groups.

1. For the oxoacid OpE(OH)q, pKa = 8-5p;

2. The successive pKa values of polyprotic acids (those with q>1) increase by 5 units for each successive proton transfer

Front 26

Difference between an acidic and basic oxide

Back 26

An acidic oxide is an oxide that, when dissolved in water, binds a water molecule and releases a proton in the surrounding solvent. A basic oxide is an oxide to which a proton is transferred when it dissolves in water

Front 27

What is the general rule to tell when an oxide is basic or acidic.

Back 27

Metals form basic oxides, while nonmetals form acidic oxides

Front 28

Amphoteric oxide

Back 28

An oxide that reacts with both acids and bases. These are formed by elements in the frontier between metals and nonmetals in the periodic table.

Front 29

What are some elements that form amphoteric oxides?

Back 29

The lighter elements of groups 2 and 13, as well as the heavier elements of groups 14 and 15

Front 30

Define complex formation

Back 30

The simplest Lewis acid-base reaction in the gas phase or noncoordinating solvents. The reactions involve Lewis acids and bases that are independently stable in the gas phase or in solvents that do not form complexes with them. The reaction is exothermic because the new bonds only fill up the bonding orbitals.

Front 31

Define displacement reactions

Back 31

A reaction in which an acid or base drives out another acid or base from a Lewis complex. This is the type of reaction that all Bronsted proton transfer reactions undergo.

Front 32

Define metathesis reactions

Back 32

A metathesis reaction is a displacement reaction assisted by the formation of another complex. It is also known as a double displacement reaction

Front 33

How are hard and soft acids and bases identified empirically

Back 33

By the trends in stabilities of the complexes that they form: hard acids tend to bind to hard bases and soft acids tend to bind to soft bases

Front 34

Order of heat of formation for hard acids

Back 34

I⁻ < Br⁻ < Cl⁻ << F⁻,

R₂S < R₂O,

PR₃ < NR₃,

Front 35

Order of heat of formation for soft acids

Back 35

F⁻ << Cl⁻ < Br⁻ < I⁻,

R₂O < R₂S,

NR₃ < PR₃,

Front 36

What types of interactions do hard and soft acids tend to have

Back 36

Soft acids & bases tend to have covalent interactions, while hard acids & bases tend to have polar interactions

Front 37

What is an exception to the general tendencies of interactions between hard and soft acids?

Back 37

HF (even though it is a hard acid, it has covalent interactions)

Front 38

What charge can a cation have to guarantee that it easily forms a complex with F?

Back 38

A +3 charge

Front 39

Define super base & provide example

Back 39

A base that is stronger than the hydroxide ion. However, formally, it is defined as a compound having a very high basicity. Examples include potassium tert-butoxide (KOC[CH₃]₃) and Lithium nitride (Li₃N)

Front 40

Define super acid & provide example

Back 40

An acid with an acidity greater than that of 100% pure sulfuric acid. An example is fluorosulfuric acid (HSO₃F)

Front 41

What are some examples of hard acid cations

Back 41

Group 1, group 2, Cr²⁺, Cr³⁺, Al³⁺, SO₃, BF₃

Front 42

Where are most of the soft acid cations?

Back 42

Groups 10-12

Front 43

What are some examples of borderline acids (list at least 4 out of 8)

Back 43

Fe²⁺, Co²⁺, Ni²⁺, Cu²⁺, Zn³⁺, Pb²⁺, SO₂, BBr₃

Front 44

Sequence for the Lewis acidity of boron trihalides and reason

Back 44

BF₃ < BCl₃ < BBr₃. This trend is commonly attributed to the degree of π bonding in the planar boron trihalide.

Front 45

Example of a Lewis reaction that has a Lewis base with a molecule that can rearrange its valence electrons

Back 45

CO₂ + OH⁻ →HCO₃

Front 46

Example of a Lewis reaction that has a Lewis base with a molecule that can expand its coordination sphere

Back 46

SiF₄ + 2 F⁻ → [SiF₆]²⁻

Front 47

Example of a Lewis reaction that has a Lewis base with a metal cation

Back 47

Fe³⁺ + 6H₂O → Fe(H₂O)₆³⁺

Front 48

Example of a Lewis reaction that has a Lewis base with a molecule with an incomplete octet

Back 48

2B + 3 Br₂ → 2 BBr₃