4.4.2 Reactions of acids (must know) PAPER 1

Question 1

What is a redox reaction

Answer 1

oxidation and reduction take place at the same time in a reaction. We call this type of reaction a redox reaction

Question 2

What salt does HCl produce / hydrochloric acid

Answer 2

Chloride salts

Question 3

What salt does H2SO4 / sulfuric acid produce

Answer 3

Sulfate salts

Question 4

Iron + Hydrochloric acid producing salt equation

Answer 4

Fe + 2HCl –> H2 + FeCl2

Question 5

Zinc + Hydrochloric acid producing a salt

Answer 5

Zn + 2HCl –> ZnCl2 +H2

Question 6

Magnesium reacting with sulphuric acid to form a salt

Answer 6

Mg + H2SO4 –> MgSO4 + H2

Question 7

Zinc reacting with sulphuric acid to form a salt

Answer 7

Zn + H2SO4 –> ZnSO4 + H2

Question 8

What are acids neutralised by

Answer 8

Alkalis and bases

Question 9

Example of an alkali

Answer 9

soluble metal hydroxides

Question 10

Examples of a base

Answer 10

insoluble metal hydroxides and metal oxides

Question 11

Why are soluble metal hydroxides alkali

Answer 11

They dissolve in water to form OH- ions

Question 12

General equation for reaction of metal oxides or metal hydroxide with acid

(base and acid)

Answer 12

Acid + Metal oxide or metal hydroxide –> Salt + Water

Question 13

General equation for reaction with metal carbonate and acids

Answer 13

Metal carbonate + Acid –> Metal salt + Carbon dioxide + Water

Question 14

What salt does nitric acid form

Answer 14

Nitrate

Question 15

How can soluble salts be made

Answer 15

Soluble salts can be made from acids by reacting them with solid insoluble substances, such as metals, metal oxides, hydroxides or carbonates.
The solid is added to the acid until no more reacts and the excess solid is filtered off to produce a solution of the salt.

Question 16

What pH is neutral

Answer 16

pH 7

Question 17

What do acids produce in aqueous solutions

Answer 17

Acids produce hydrogen ions (H+) in aqueous solutions.
Aqueous solutions of alkalis contain hydroxide ions (OH–
)

Question 18

What do aqueous solutions of alkalis contain

Answer 18

Aqueous solutions of alkalis contain hydroxide ions (OH–)

Question 19

What is a pH of acids

Answer 19

Less than 7

Question 20

What is the pH of alkalis

Answer 20

More than 7

Question 21

General equation for neutralisation reactions

Answer 21

acid + alkali –> salt + water

Question 22

Equation for a neutralisation reaction with just hydrogen ions and hydroxide ions

Answer 22

H+ + OH- –> H2O

Question 23

What can you use to test the pH of a solution

Answer 23

Universal indicator

Or pH probe attached to a pH meter

Question 24

What is a titration

Answer 24

An experiment that lets you see what volume of a reactant is needed to react completely with a certain volume of another reactant

Question 25

What can you use a titration for (acids)

Answer 25

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

Question 26

Units for conc in titrations

Answer 26

mol/dm3 or g/dm3

Question 27

What are strong acids

Examples of strong acids

Answer 27

A strong acid is completely ionised in aqueous solution.

Examples of strong acids are hydrochloric, nitric and sulfuric acids.

Question 28

What are weak acids and examples

Answer 28

A weak acid is only partially ionised in aqueous solution.

Examples of weak acids are ethanoic, citric and carbonic acids.

Question 29

Is a strong or weaker acid more reactive (with same conc)

Answer 29

Strong acid

Question 30

What is the pH of a strong acid and weak acid compared to eachother with same conc

Answer 30

Strong - Lower

Weak - Higher

Question 31

How does pH and hydrogen ion conc relate

Answer 31

As the pH decreases by one unit, the hydrogen ion concentration of the solution increases by a factor of 10.

Question 32

Equation for change in H+ conc

Answer 32

Factor H+ ion changes by = 10^-x

x = difference in pH