Extraction of iron

Question 1

what is the name of the ore iron is extracted from

Answer 1

hematite

Question 2

list the raw materials in extraction of iron

Answer 2

iron oxide
coke
limestone
air

Question 3

describe stage 1

Answer 3

starting material is coke
coke is added reacting with oxygen to produce carbon dioxide
C(s) + O₂(g) → CO₂(g)

Question 4

describe stage 2

Answer 4

the carbon dioxide reacts with more oxygen to form carbon monoxide
CO₂(g) + C(s) → 2CO(g)

Question 5

describe stage 3

Answer 5

the carbon monoxide acts as a reducing agent and reduces the iron oxide to produce iron and carbon dioxide and the iron will fall to the bottom of the furnace to be tapped off or collected
Fe₂O₃(s) + 3CO(g) → 2Fe(II)(l) + 3CO₂(g)
the limestone decomposes to form calcium oxide
CaCO₃ → CaO + CO₂

the calcium oxide then reacts with impurities in the iron ore in order to remove them
CaO + SiO₂ → CaSiO₃
forming slag which will float above the iron in the blast furnace

Question 6

describe conversion of iron to steel

Answer 6

-the molten iron is an alloy of 96% iron and some impurities such as phosphorus, silicon, sulfur and carbon
-conversion happens in a tilting furnace
-the oxygen oxidises the impurities to their oxides which are acidic
-the powdered calcium oxide reacts with acidic silicon and phosphorus oxides to form slag
CaO(s) + SiO₂(l) → CaSiO₃(s)

Question 7

where does waste gas go out

Answer 7

the top of the furnace

Question 8

where does hot air go in

Answer 8

the bottom of the furnace

Question 9

give two reasons why coke is used in extraction of iron

Answer 9

1- it is a source of energy

2- reduction of iron oxides