Acids And Bases - Lecture 15

Question 1

What is an Arrhenius acid?

Answer 1

Substances that contain hydrogen and dissociates in water to form a hydrogen ion

Question 2

What is an Arrhenius base?

Answer 2

Substances that contain the hydroxyl group (OH) and dissociates in water to form a hydroxide ion and a cation

Question 3

What does an Acid produce according to the theory of Arrhenius in water

Answer 3

H+ ion (proton)

Question 4

What does a base produce according to the theory of Arrhenius in Water?

Answer 4

OH- ion (hydroxide ion)

Question 5

What is a strong acid according to Arrhenius?

Answer 5

Completely dissociates/fully ionised in solution and produces a lot of Hydrogen ions (H+)

Question 6

What is a weak acid according to Arrhenius?

Answer 6

Is one that is only partially ionised/slightly dissociates in water and produces only a few H+ Ions (hydrogen ions)

Question 7

Examples of strong acids according to Arrhenius?

Answer 7

Hydrochloric acid , Sulphuric acid, hydrobromic acid, hydroiodic (hydriodic) acid, nitric acid and perchloric acid

Question 8

Examples of weak acids according to Arrhenius

Answer 8

Hydrofluoric acid, hydrosulfuric acid, hydrocyanic acid, acetic acid (ethanoic acid)

Question 9

Monoprotic Acids

Answer 9

Acids that produce only one proton (H+) when dissolved in water

Question 10

Polyprotic Acids

Answer 10

Acids that produce more than one H+ ion in water

Question 11

Strong base according to Arrhenius

Answer 11

Strong electrolyte, which is completely ionised/completely dissociates in water (aqueous solution) to produce hydroxide ions (OH-)

Question 12

Weak base according to Arrhenius

Answer 12

Only partially ionise/slightly dissociate in water to produce OH- ions (hydroxide ions)

Question 13

Acid + Base =

Answer 13

Salt + Water

Question 14

Base that dissolves in Water is called an

Answer 14

Alkali

Question 15

Acid + Metal =

Answer 15

Salt + Hydrogen

Question 16

Acids + Metal Carbonate =

Answer 16

Salt + Water and CO2 gas given off

Question 17

Acids and Bases are

Answer 17

Electrolytes

Question 18

Neutralisation

Answer 18

Reaction between an acid and a base to form a salt and water

Question 19

Why does Neutralisation Occur?

Answer 19

Hydrogen ions (H+) and hydroxide ions (OH-) react to produce water

Question 20

State 3 limitations of the Arrhenius theory of acids and bases

Answer 20

1. Limited to acid-base reactions that place in water
2. Restricts acids to hydrogen containing species and bases to hydroxide containing species
3. Does not explain how certain substances can be amphoteric

Question 21

Amphoteric

Answer 21

Substance that can act as both an acid and a base

Question 22

Bronsted Lowry acid

Answer 22

Proton donor (H+)

Question 23

Bronsted Lowry Base

Answer 23

Proton (H+) acceptor (must contain lone pair of electrons)

Question 24

Conjugate pair

Answer 24

A pair of substances, an acid and a base, that differ by one H+

Question 25

Conjugate Acid

Answer 25

Base + Hydrogen ion (H+)

Question 26

Conjugate Base

Answer 26

Acid - Hydrogen ion (H+)

Question 27

According to BL theory, acids may be

Answer 27

Cations, neutral molecules or anions

Question 28

According to BL theory, bases may be

Answer 28

Anions or neutral molecules

Question 29

Is water an amphoteric substance

Answer 29

Yes

Question 30

Protophilic solvents

Answer 30

Act as proton acceptors (bases)

Question 31

Protogenic solvent

Answer 31

Proton donors (acids)

Question 32

Amphiprotic Solvents

Answer 32

Act as an acid or base (water, alcohol)

Question 33

Aprotic Solvents

Answer 33

Solvents which will neither donate nor accept protons Eg.// benzene, carbon tetrachloride

Question 34

Lewis Acid

Answer 34

Electron pair acceptor

Question 35

Lewis Base

Answer 35

Electron pair donor

Question 36

Acid according to Lewis

Answer 36

Substance that can accept a pair of electrons from another atom to form a new bond

Question 37

Base according to Lewis

Answer 37

Substances that can donate an electron pair to another atom to form a new bond

Question 38

Lewis definition includes

Answer 38

Metal ions and other electron pairs as acids

Question 39

Lewis acid …..

Answer 39

Has an empty atomic orbital of low energy that can accommodate a pair of electrons

Question 40

The process of neutralisation of a Lewis Base forms

Answer 40

Coordinate Covalent bond between an acid and base

Question 41

The product of Lewis Acid-Base reaction is referred to as

Answer 41

Adduct

Question 42

Example of Lewis acid-base adducts

Answer 42

Complex ions

Question 43

Advantages of Lewis Theory

Answer 43

1. Expands acid base reactions to include ,any substances without H in the formula 2. Used to explain the effect of compounds which act as an acid in nonaqueous organic solvents

Question 44

Limitation of Lewis Theory

Answer 44

1. Includes all the coordination reactions and coordination compounds which may not always be true 2. Cannot explain the behaviour of well known protonic acids which do not form coordination bonds with bases 3. Relative strengths of acids and bases cannot be explained by this theory