Chapter 4 - Acids and redox

Question 1

What is an acid?

Answer 1

It is a H+ (proton) donor

Question 2

What will be produced when a strong acid reacts with water?

Answer 2

H3O (proton + water)

Question 3

What are bases?

Answer 3

Proton acceptors

Question 4

Formula of sulfuric acid

Answer 4

H2SO4

Question 5

Formula of hydrochloric acid

Answer 5

HCl

Question 6

Formula of nitric acid

Answer 6

HNO3

Question 7

Formula of ethanoic acid

Answer 7

CH3COOH

Question 8

What will the salt of hydrochloric acid look like?

Answer 8

xCl

Question 9

What will the salt of sulfuric acid look like?

Answer 9

X2SO4

Question 10

What will the salt of nitric acid look like?

Answer 10

x(NO3)2

Question 11

Formula of sodium hydroxide

Answer 11

NaOH

Question 12

Formula of potassium hydroxide

Answer 12

KOH

Question 13

Formula of ammonia

Answer 13

NH3

Question 14

What is a strong acid?

Answer 14

One which fully dissociates in water

Question 15

What is a weak acid?

Answer 15

One which partially dissociates in water - this reaction is reversible

Question 16

What is produced when ammonia reacts with an acid?

Answer 16

Ammonium salt

Question 17

What are titrations used for?

Answer 17

To find out how much acid is needed to neutralise a known quantity of alkali

Question 18

Where must we read the results of a titration from?

Answer 18

The meniscus

Question 19

Top tips for titrations

Answer 19

Balance the equation
Work out moles of known substance
Work out moles of unknown substance
Work out concentration or volume of unknown

Question 20

What colour change indicates a titration is over?

Answer 20

Pink to colourless when acid is added to alkali

Question 21

What is a standard solution?

Answer 21

One with a known concentration

Question 22

Equation for number of moles in a solution

Answer 22

Number of moles = concentration x volume

Question 23

How to prepare a standard solution

Answer 23

Weigh out an exact amount of solid using a balance
Add water to the beaker to dissolve the solid
Transfer to a volumetric flask and top up with water until it meets the graduation line
Thoroughly mix the solution

Question 24

What are polyprotic acids?

Answer 24

Acids that donate more than one electron

Question 25

What is important to remember about di and tri protic acids?

Answer 25

They will take double or triple the numbers of moles of base to be neutralised

Question 26

What is the oxidation number?

Answer 26

How many electrons need to be donated or accepted to form a compound or ion

Question 27

What will all pure elements have an oxidation number of?

Answer 27

0

Question 28

What will ions consisting of one ion have the oxidation number of?

Answer 28

The charge of the ion

Question 29

For moleular ions, what will the sum of the oxidation numbers equal?

Answer 29

The overall charge of the ion

Question 30

Oxidation number of oxygen

Answer 30

-2

Question 31

Oxidation number of hydrogen

Answer 31

+1

Question 32

Oxidation number of fluorine

Answer 32

-1

Question 33

How can roman numerals help us with the oxidation number?

Answer 33

The numeral next to an element shows its oxidation number - Fe (II) has an oxidation number of +2

Question 34

What do -ate compounds contain?

Answer 34

Oxygen and another element

Question 35

What does the number after the non-oxygen element in an -ate compound show us?

Answer 35

Its oxidation number

Question 36

What is a loss of electrons called?

Answer 36

Oxidation

Question 37

What is a gain of electrons called?

Answer 37

Reduction

Question 38

What will happen to the oxidation number as electrons are lost?

Answer 38

It will increase

Question 39

How to remember oxidation and reduction

Answer 39

OIL RIG

Question 40

What happens to metals when they react with acids?

Answer 40

They are oxidised

Question 41

What is produced when a base neutralises an acid?

Answer 41

A salt

Question 42

What is an alkali?

Answer 42

A base that dissolves in water and releases hydroxide ions

Question 43

What is formed when an acid reacts with a metal hydroxide or oxide?

Answer 43

A salt and water

Question 44

What is produced when an acid and an alkali react?

Answer 44

A salt and water

Question 45

What is produced when an acid reacts with a metal carbonate?

Answer 45

A salt, water and carbon dioxide

Question 46

What will the oxidation number for all elements be?

Answer 46

0

Question 47

Where does the sign go when writing an oxidation number?

Answer 47

Before the number

Question 48

What is a salt?

Answer 48

The metal ion is replaced by a hydrogen ion

Question 49

What is the difference between a base and an alkali?

Answer 49

A base accepts H+ ions from an acid and an alkali releases OH- ions into solution