C3.3 - types of chemical reactions

Question 1

what is neutralisation? (2)

Answer 1

the reaction between acids and a base/alkali (1) to form a salt and water only (1)

Question 2

does the pH of the solution change during neutralisation?

Answer 2

yes, depending on the concentration of acid/alkali

Question 3

what salt is produced when copper oxide powder neutralises sulfuric acid?

Answer 3

copper sulfate

Question 4

what are the products produced during the neutralisation of:
sodium hydroxide + hydrochloric acid ->

Answer 4

sodium chloride + water

Question 5

what is the equation during the reaction of an acid and a metal carbonate?

Answer 5

acid + carbonate -> salt + water + carbon dioxide

Question 6

what are the products of the following reaction:
hydrochloric acid + calcium carbonate ->

Answer 6

calcium chloride + water + carbon dioxide
(metal carbonate)

Question 7

what is the word equation during the reaction of a metal oxide and an acid?

Answer 7

Acid + oxide → salt + water

Question 8

what are the products of the following reaction:

hydrochloric acid + magnesium oxide ->

Answer 8

magnesium chloride + water.

Question 9

what is the word equation of the reaction between a metal hydroxide and acid?

Answer 9

hydroxide + acid -> salt + water

Question 10

what happens during neutralisation in solution?

Answer 10

• acidic solutions contain H+ ions (hydrogen)
• alkaline solutions contain OH- ions (hydroxide)
• they both react together and produce water

Question 11

what is a redox reaction?

Answer 11

a reaction where reduction and oxidation happens at the same time

Question 12

what is reduction in terms of oxygen?

Answer 12

loss of oxygen

Question 13

what is oxidation in terms of oxygen?

Answer 13

gain of oxygen

Question 14

looking at the following equation what is the oxidising and reducing agent and why? (4)

aluminium + iron oxide -> aluminium oxide + iron

Answer 14

iron oxide is the oxidising agent (1) as is loses/donates oxygen (to aluminium to make aluminium oxide) (1)

aluminium is the reducing agent (1) as it gains/receives oxygen (from iron oxide) (1)

Question 15

what is the mnemonic for remembering oxidation/reduction/ electrons etc.?

Answer 15

OIL RIG
-> oxidation is loss
-> reduction is gain

Question 16

do redox reactions always have to involve oxygen?

Answer 16

no, it can just be a loss/gain of electrons

Question 17

what is an acid? (in terms of what it releases when dissolved in water)

Answer 17

a substance which releases hydrogen ions when dissolved in water

Question 18

what makes a solution acidic?

Answer 18

hydrogen ions

Question 19

what is a base?

Answer 19

a substance that can neutralise acids

Question 20

what does an alkali release when dissolved in water?

Answer 20

OH- ions

Question 21

what makes a solution alkaline?

Answer 21

hydroxide ions

Question 22

what does pH < 7 mean?

Answer 22

acidic

Question 23

what does pH = 7 mean?

Answer 23

neutral

Question 24

what does pH > 7 mean?

Answer 24

alkaline

Question 25

what do you use to show the pH of a solution?

Answer 25

- universal indicator - pH meter

Question 26

what are carbonates?

Answer 26

ionic compounds that contain the carbonate ion (CO3 2-)

Question 27

what do carbonates form when react with acids?

Answer 27

salt + water + carbon dioxide

Question 28

what is produced when a metal reacts with an acid?

Answer 28

salt + hydrogen

Question 29

what salt is produced when magnesium and hydrochloric acid reacts together?

Answer 29

magnesium chloride

Question 30

why does a piece of magnesium ribbon appear to have dissolved if placed into hydrochloric acid?

Answer 30

- hydrogen (from HCl) is released as bubbles - salt magnesium chloride (from both) is formed

Question 31

what is a dilute acid?

Answer 31

an acid which contains a low ratio of acid to volume of solution

Question 32

what is a concentrated acid?

Answer 32

an acid which contains a high ratio of acid to volume of solution

Question 33

what is a weak acid?

Answer 33

acids that partially ionise (not all molecules release H+ ions)

Question 34

what is a strong acid?

Answer 34

acids that fully ionise (all molecules release H+ ions)

Question 35

what does a pH titration curve show?

Answer 35

the effect on pH by adding different amounts of acid to an alkali solution or vice versa