Salts and electrolysis

Question 1

What is an aqueous solution?

Answer 1

A substance dissolved in water

Question 2

What are alkalis?

Answer 2

Soluble hydroxides

Question 3

What are bases?

Answer 3

Substances that can neutralise acids

Question 4

What is neutral?

Answer 4

Pure water

Question 5

What makes a solution acidic?

Answer 5

H+ ions

Question 6

What ions do all alkalis form when we add them to water?

Answer 6

OH- ions

Question 7

How do we make salts?

Answer 7

acid + metal ——> a salt + hydrogen

Question 8

When salts are formed by neutralising hydrochloric acid what are they?

Answer 8

Chlorides

Question 9

When an acid reacts with an alkali what reaction takes place?

Answer 9

A neutralisation reaction

Question 10

Give the general equation for a neutralisation reaction

Answer 10

Acid + Alkali —–> salt + water

Question 11

When a neutralisation reaction happens what two ions react with eachother?

Answer 11

H+ and OH-

Question 12

When we react an acid with an alkali how do we know when the acid is completely reacted?

Answer 12

We use an indicator

Question 13

Name a salt that is used as a fertiliser to provide crops with nitrogen?

Answer 13

Ammonium nitrate

Question 14

What is an insoluble solid?

Answer 14

A precipitate

Question 15

How are soluble salts made?

Answer 15

Acids reacting with either; metals, insoluble bases or alkalis

Question 16

What’s the problem with reacting acids and metals?

Answer 16

Not all metals are suitable, some are too reactive and some are not reactive enough

Question 17

When an insoluble base is added to the acid what happens?

Answer 17

It’s added until no more can react and the excess solid is filtered off

Question 18

What shows that an the acid and alkali have completely reacted to produce a salt solution?

Answer 18

An indicator

Question 19

What can we do to salt solutions to produce solid salts?

Answer 19

Crystalise them

Question 20

How are insoluble salts made?

Answer 20

Mixing solutions of ions so precipitate is formed

Question 21

Name two bases.

Answer 21

Metal oxides and hydroxides

Question 22

The salt produced in any reaction between

an acid and a base or alkali depends on…

Answer 22

The acid used and the metal in the base

Question 23

When ammonia dissolves in water what does it produce?

Answer 23

An alkaline solution

Question 24

Why are ammonium salts important?

Answer 24

For fertilisers

Question 25

What kind of ion is H+

Answer 25

Hydrogen ions

Question 26

What kind of ion is OH-

Answer 26

Hydroxide ions

Question 27

Which ion makes solutions acidic?

Answer 27

Hydrogen ions

Question 28

Which ion makes solutions alkaline?

Answer 28

Hydroxide ions

Question 29

What happens in neutralisation reactions?

Answer 29

Hydrogen ions react with Hydroxide ions to produce water

Question 30

What happens to the ions when an ionic substance is melted or dissolved in water?

Answer 30

The ions are free to move around in the solution

Question 31

What is electrolysis?

Answer 31

Passing an electric current through ionic substances | that are molten to break them down into elements

Question 32

During electrolysis where to positively and negatively charged ions go?

Answer 32

Positively charged ions move to the negative electrode | Negatively charged ions move to the positive electrode

Question 33

What is an electrolyte?

Answer 33

A substance broken down by electrolysis

Question 34

What is electrolysis used for?

Answer 34

To electroplate objects

Question 35

At the negative electrode what happens to positive ions?

Answer 35

Gain electrons (reduction)

Question 36

At the positive electrode what happens to negative ions?

Answer 36

Lose electrons (oxidisation)

Question 37

How is aluminium constructed?

Answer 37

By the electrolysis of aluminium oxide and cryolite (molten mixture)