Extracting Ores

Question 1

What are ores

Answer 1

minerals with enough metal so that it can be economically extracted

Question 2

Give an example of an ore

Answer 2

Haemaetite-iron ore Bauxite-Aluminium ore

Question 3

What is meant by an uncombined element?

Answer 3

A pure element found in native ground

Question 4

Give an example of an uncombined element

Answer 4

Gold or silver

Question 5

Which metals are extracted using carbon extraction

Answer 5

The metals which are less reactive than carbon, specifically zinc iron and lead

Question 6

Where are these metals in the reactivity series relative to carbon

Answer 6

All below carbon

Question 7

Which metals are extracted using electrolysis

Answer 7

Those above carbon, specifically potassium, sodium, lithium, magnesium, calcium, aluminium

Question 8

where are these metals relative to hydrogen in the reactivity series

Answer 8

all above hydrogen

Question 9

What are the three raw materials that go into the blast furnace

Answer 9

Iron ore, coke and limestone

Question 10

What are the three reactions that make iron

Answer 10

Carbon + oxygen –> carbon dioxide
C + O2 –> CO2

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

Iron oxide + carbon monoxide –> iron + carbon dioxide
Fe2O3 +3CO –> 2Fe + 3CO2

Question 11

What are the two reactions that make slag

Answer 11

Calcium carbonate –> calcium oxide + carbon dioxide
CaCO3 + CaO + CO2

Calcium oxide + silicone dioxide –> calcium silicate
CaO + SiO2 –> CaSiO3

Question 12

Why is the pig iron from the blast furnace useless

Answer 12

Since it has so much carbon in it (4%) it is brittle

Question 13

What is done to make it useful

Answer 13

It is turned into steel using the Basic Oxygen Steel making process - this removes most of the carbon

Question 14

what is the ore of aluminium

Answer 14

Bauxite

Question 15

what is Bauxite mixed with before electrolysis

Answer 15

Cryolite

Question 16

Why do we mix bauxite and cryolite

Answer 16

To lower the melting point OF THE MIXTURE to a practical level (900 degrees rather than over 2000 degrees - costs less)

Question 17

Which electrode does the aluminium form on

Answer 17

Cathode (negative end)

Question 18

During electrolysis, what forms on the anode (positive) side

Answer 18

Oxygen

Question 19

What does oxygen do to the electrode

Answer 19

It burns away as it reacts with carbon

Question 20

Write an equation to show the overall reaction of aluminium’s formation in electrolysis

Answer 20

Aluminium oxide –> aluminium + oxygen

Question 21

What is an alloy

Answer 21

An alloy is a mixture of a metal and one or more elements

Question 22

Give an example of some alloys and their composition of elements

Answer 22

Brass - Copper (67%) & Zinc (33%)
Solder - Tin (80%-31%) & Lead (20%-69%)
Steel- Iron (99%) & Carbon (1%)

Question 23

Explain using diagrams why alloys are harder than pure metals

Answer 23

• Pure metal has regular layers
• These layers can slide over each other when a force is applied
• In an alloy the layers are distributed by the addition of other elements atoms consequently stopping the layers from sliding