Metal Extraction

Question 1

What is an ore?

Answer 1

A metal rock/substance from which it is economically viable to extract the metal and contains enough metal to make extraction worthwhile

Question 2

What is the name for Silver, Gold and Platinum in the reactivity series?

Answer 2

Native Metals

Question 3

Why are these 3 metals called ‘native metals’ ?

Answer 3

Because they are unreactive and are found just as they are in the earths crust

Question 4

How do metals above silver in the reactivity series need to get extracted?

Answer 4

They need to get extracted from their ores

Question 5

How do elements above Carbon need to get extracted?

Answer 5

They get extracted using electrolysis

Question 6

How do elements below Carbon need to be extracted?

Answer 6

They are extracted by reduction using carbon

Question 7

What is electrolysis?

Answer 7

Splitting up using electricity

Question 8

What is a disadvantage of extracting a metal using electrolysis?

Answer 8

It is much more expensive than reduction with carbon because it uses a lot more energy

Question 9

Why is copper purified by electrolysis?

Answer 9

~ Copper is extracted for its ore using carbon (the ore is heated in a furnace ‘smelting’
~ The copper produced is too impure to use as it doesn’t conduct electricity
~ So electrolysis is used to purify the copper and remove the impurities so that it can be used

Question 10

What is the name of the liquid which conduct the electricity in electrolysis?

Answer 10

The electrolyte

Question 11

What does the electrolyte (liquid) contain to conduct the electricity?

Answer 11

Free ions which pass on the electrical charge

Question 12

In electrolysis what charges attract?

Answer 12

Opposite charges

Question 13

What is a displacement reaction?

Answer 13

A reaction by which a less reactive metal gets displaced (removed) by a more reactive metal

Question 14

What is bioleaching?

Answer 14

The process in which bacteria separates the copper from copper sulfide
~ The bacteria gets energy from the bond between the copper and the sulfur, separating the copper from its ore in the process
~ The leachate contains copper which can be extracted

Question 15

What is phytomining?

Answer 15

Growing plants in soil that contains copper
~ The plants can’t get rid/use the copper so it builds up in the leaves
~ The plant can be harvested, dried and burned in a furnace
~ The copper can be collected from the ash left in the furnace

Question 16

Give two advantages and disadvantages of metal extraction (mining ores) on the environment

Answer 16

Advantage:
~ mining metal ores means useful products can be made and provides local people with jobs bringing money into the area

Disadvantage:
~ mining ores is bad for the environment (causes nice and the destruction of habitats). Deep mine shafts can also be dangerous for a long time after the mine has been abandoned

Question 17

Why are recycling metals important?

Answer 17

~ Mining/extracting metals takes lots of energy which comes from burning fossil fuels
~ Fossil fuels are running out so it is vital that we conserve them, it also contributes to global warming, acid rain and global dimming
~ Energy doesn’t come cheap so recycling metals also saves money too