C1.3

Question 1

What is bioleaching?

Answer 1

~ Bacteria is used to grow on the low grade copper ore
~ Bacteria produce a solution as a by-product
~ The solution can then go through electrolysis or displacement to extract the metal

Question 2

How does electrolysis work?

Answer 2

~ Two electrodes are added to a solution in the form of a salt
~ Positive ions are attracted to negative electrode
~ Negative ions are attracted to positive electrode
~ Metal can then be removed

Question 3

What is displacement?

Answer 3

~ Scrap iron is put in a solution of a metal salt
~ Metal will coat itself around the outside of the scrap iron
~ Metal can then be extracted

Question 4

What is the difference between low carbon steel and high carbon steel?

Answer 4

~ Low carbon steel is easy to shape

~ High carbon steel is hard and resistant to corrosion

Question 5

What does steel and chromium produce?

Answer 5

Stainless steel

Question 6

Why is stainless steel useful?

Answer 6

~ Doesn’t rust
~ Not very reactive
~ Not corrosive

Question 7

Why are metals such as aluminium and gold turned into alloys with copper?

Answer 7

~ Makes them harder

~ Less expensive

Question 8

What is an ore?

Answer 8

A type of rock containing a metal that’s economically worth extracting

Question 9

Why are phytomining and bioleaching important?

Answer 9

They produce the pure metal from low grade ores

Question 10

Give the symbol equation for a reduction reaction using carbon and a metal ore

Answer 10

2FeO + C -> 2Fe + CO2

Question 11

What is Phytomining?

Answer 11

Where plants are absorbed to make metal compounds. Plants are then burned and the metal can be separated out from the ash produced

Question 12

What metals can be extracted using reduction?

Answer 12

Those below carbon in the reactivity series

Question 13

How is phytomining done?

Answer 13

~ By growing a certain type of plant on low grade copper ore
~ Some plants have the ability to take out the metal compounds from the ore and take it into their body tissue
~ The plants are then taken and burnt
~ Ash remains contain the metal which can be extracted using electrolysis or displacement

Question 14

What are some properties of titanium and aluminium?

Answer 14

~ Low density

~ Resistant to corrosion

Question 15

What are some properties of copper?

Answer 15

~ Good conductor of heat and electricity
~ Malleable
~ Not reactive with water, so can be used in piping

Question 16

What is an alloy?

Answer 16

A mixture of metals

Question 17

Why is 100% pure metal not useful?

Answer 17

Too soft

Question 18

What is wrong with impure iron?

Answer 18

~ Brittle

~ Strong so can’t get compressed

Question 19

What is in the blast furnace?

Answer 19

~ Coke
~ Limestone
~ Iron oxide

Question 20

Where is iron produced?

Answer 20

In a structure called the Blast Furnace

Question 21

What is the first step to extracting metals?

Answer 21

Concentrating the ore, which removes some impurities and makes the ore have more metal inside

Question 22

Why are there problems with extracting copper?

Answer 22

~ Carbon reacting with copper produces impure copper so electrolysis must be used to make it pure
~ Copper rich ores are running out, making it expensive

Question 23

How are metals above carbon in the reactivity series extracted?

Answer 23

~ The ore is melted

~ Electricity is used to separate the metal and oxygen

Question 24

Why is no reaction required to remove oxygen from gold?

Answer 24

It’s so unreactive that it’s not found as an oxide, and can be found native in the ground

Question 25

How can a metal which is below carbon in the reactivity series be extracted?

Answer 25

It's reacted with carbon because the carbon takes the oxygen from the metal

Question 26

How can low grade ore be extracted?

Answer 26

Phytomining / bioleaching

Question 27

How can high grade ores be extracted?

Answer 27

Smelting, then electrolysis / displacement

Question 28

What are the properties of transition metals?

Answer 28

~ Good conductors of heat and electricity | ~ Malleable

Question 29

Why are gold, aluminium and copper not useful alone, and how can they be made more useful?

Answer 29

~ They're too soft | ~ They can be mixed with other metals to make them harder

Question 30

What is a use of titanium?

Answer 30

To make hip joints

Question 31

What are some uses of aluminium?

Answer 31

~ Aeroplane bodies | ~ Power lines

Question 32

What are some uses of copper?

Answer 32

~ Cooking pots and pans | ~ Piping

Question 33

Why should we recycle metals?

Answer 33

~ To save money and energy ~ To ensure all natural resources don't get used up ~ To reduce the amount of mining which damages the environment