Chemistry In Industry (5)

Question 1

Most metals can’t be found as pure lumps. You have to __________ them from a ___________

Answer 1

Extract

Compound

Question 2

Most metals are found in ________

Answer 2

Ores

Question 3

Metals that are unreactive don’t tend to form ____________ with other elements

Answer 3

Compounds

Question 4

Unreactive metals such as _______ are found uncombined

Answer 4

Gold

Question 5

Most metals do react with other elements to form ______________, which can be found naturally in the Earth’s __________

Answer 5

Compounds

Crust

Question 6

If a compound contains enough of the metal to make it worthwhile extracting, the compound is called a metal _____

Answer 6

Ore

Question 7

There are _____________ amounts of metals ores - they’re finite resources

Answer 7

Limited

Question 8

The more reactive a metal is, the ___________ it is to extract it from a compound

Answer 8

Harder

Question 9

Metals often have to be separated from their _________

Answer 9

Oxides

Question 10

Lots of common metals, like iron and aluminium, react with oxygen to form ___________

Answer 10

Oxides

Question 11

Oxides are often like the ______ that the metals need to be extracted from

Answer 11

Ores

Question 12

A reaction that separates a metal from the oxygen in its oxide is called a ___________ reaction

Answer 12

Reduction

Question 13

In a reduction reaction, what is the substance that reduces the metal (and is oxidised) called

Answer 13

A reducing agent

Question 14

What is the most common type of reduction reaction

Answer 14

Using carbon as a reducing agent to separate the oxygen from the metal. But metals can’t be used for all metals

Question 15

How are metals which are lower in the reactivity series than carbon extracted

Answer 15

With carbon
This is done by heating the ore with carbon monoxide. Because carbon takes the oxygen away from metals which are less reactive than itself.

Question 16

________ reactive elements form compounds more readily

Answer 16

More

Question 17

Very reactive metals form very __________ ores. I.e it’s difficult to get the metal out of the compound

Answer 17

Stable

Question 18

Metals that are more reactive than carbon have to be extracted using ______________

Answer 18

Electrolysis

Question 19

Aluminium is more reactive than carbon so it has to be extracted from its ore using ________________

Answer 19

Electrolysis

Question 20

Aluminium’s main ore is bauxite, after mining and purifying, a __________ powder is left. This is pure aluminium oxide ________

Answer 20

White

Al2O3

Question 21

Al2O3 has a very high melting point so melting it would be very expensive. Instead the aluminium oxide is dissolved in molten ___________. This brings the temperature down making it easier and cheaper. The _____________ are made of graphite, a good conductor of electricity.

Answer 21

Cryolite

Electrodes

Question 22

Electrolysis - turning ions into the ________ you want

Answer 22

Atoms

Question 23

Molten aluminium oxide contains free ions - this means it’ll …

Answer 23

Conduct electricity

Question 24

The positive Al3+ ions are attracted to the ____________ electrode where they ________ electrons and turn into ______________ atoms. These then sink to the bottom.

Answer 24

Negative
Gain
Aluminium

Question 25

The negative O2- ions are attracted to the ___________ electrode where they ________ electrons. These oxygen atoms will then react together to form _____ or with the carbon anode as well to form ______

Answer 25

Positive Lose O2 CO2

Question 26

As the positive ___________ electrode is constantly getting worn down by oxygen, it often needs ____________

Answer 26

Carbon | Replacing

Question 27

What is a redox reaction

Answer 27

Where both reduction and oxidation take place

Question 28

Equation for the decomposition of aluminium:

Answer 28

Aluminium oxide --> Aluminium + Oxygen

Question 29

Decomposition of aluminium: Reaction at the negative electrode:

Answer 29

Al3+ + 3E- --> Al

Question 30

Decomposition of aluminium: Reaction at the positive electrode:

Answer 30

2O2- --> O2 + 4E-

Question 31

What is reduction

Answer 31

A gain of electrons

Question 32

What is oxidation

Answer 32

A loss of electrons

Question 33

Electrolysis uses a lot of _____________ which makes it expensive. Energy is also needed to _______ the electrolyte mixture. This is also expensive. The disappearing __________ electrodes need frequent replacement. This is expensive too.

Answer 33

Electricity Heat Positive

Question 34

Iron is extracted from haematite by __________ in a blast furnace

Answer 34

Reduction

Question 35

What are the 3 raw materials

Answer 35

Iron Ore Coke Limestone

Question 36

The iron ore contains the iron The coke is almost pure ___________. This is for reducing the iron oxide to iron _________. What does the limestone do?

Answer 36

Carbon Iron metal Takes away impurities in the form of slag

Question 37

Hot air is blasted into the furnace, making the ________ burn much faster than normal. This raises the temperature to about ______°C

Answer 37

Coke | 1500

Question 38

The coke burns and produces what? | Equation:

Answer 38

Carbon dioxide | C + O2 --> Co2

Question 39

The Co2 then reacts with unburnt coke to form what? | Equation:

Answer 39

CO CO2 + C --> 2CO Carbon dioxide + carbon --> carbon monoxide

Question 40

The carbon monoxide then reduces the iron ore to what? | Equation:

Answer 40

Iron | Carbon monoxide + iron(|||) oxide --> carbon dioxide + iron

Question 41

The iron is __________ at this temperature and also very dense so it runs straight to the bottom where it's tapped off

Answer 41

Molten

Question 42

What is the main impurity of iron | What removes it

Answer 42

Sand (Silicon dioxide) | Removed by limestone

Question 43

The limestone is decomposed by the heat into what

Answer 43

Calcium oxide and CO2

Question 44

The limestone is decomposed by the heat into calcium oxide and CO2. This calcium oxide then reacts with the sand to form what?

Answer 44

Calcium silicate, or slag which is molten and can be tapped off

Question 45

Calcium oxide reacting with calcium silicate equation:

Answer 45

CaO + Sio2 --> Casio3 (molten slag)

Question 46

Cooled slag is solid and is then used for what?

Answer 46

Road-building | Fertiliser

Question 47

Name 5 properties which iron and aluminium have in common

Answer 47

``` Both dense and lustrous (shiny) Both have high melting points Both strong and hard to break Both malleable Both good conductors of electricity and heat energy too ```

Question 48

Adding other materials to iron can change its ______________. This makes it really useful. It makes it suitable for lots of different uses

Answer 48

Properties

Question 49

Wrought iron is almost completely _______. Name its main property and use

Answer 49

Pure Its malleable Used to make ornamental gates and railings

Question 50

You can mix iron with other elements to make __________

Answer 50

Alloys

Question 51

Cast iron is very hard but _________. | What is it a mixture of?

Answer 51

Brittle | Iron, carbon and silicon

Question 52

What is cast iron used for

Answer 52

Some cooking pans

Question 53

Steel is an alloy made of mainly ________ and __________. It is ___________ than pure iron, but it can still be hammered easily into sheets and welded together. These properties mean that steel is great for making what

Answer 53

Iron, carbon Harder Car bodies

Question 54

What is the main problem with iron

Answer 54

That it rusts

Question 55

Stainless steel is an alloy made of chromium that doesn't rust. What's it used for

Answer 55

Knives, forks and cooking pans.

Question 56

Aluminium is a typical metal. However, unlike iron, it doesn't ___________ easily.

Answer 56

Corrode

Question 57

Aluminium reacts very ___________ with oxygen in the air to from what? A protective layer of aluminium _________ sticks firmly to the aluminium below and stops any further __________ from taking place

Answer 57

Quickly Aluminium oxide Reaction

Question 58

Because aluminium doesn't __________ it's useful for products that come on contact with __________. E.g. drink cans - you wouldn't want rust in your drink.

Answer 58

Corrode | Water

Question 59

Aluminium is much less dense than iron which makes it ___________. This makes it useful when weight of the metal is important, e.g. aeroplanes.

Answer 59

Lighter

Question 60

What is Casio3 the formula of

Answer 60

Molten slag