10.3 Extraction of Metals

Question 1

Describe the extraction of iron from hematite

Answer 1

Charge (coke, iron ore, limestone) is added through the top of the furnace

Coke burns in hot air blown from the bottom of the furnace
C + O2 → CO2

Carbon dioxide reacts with coke
CO2 + C → 2CO

Carbon monoxide reduces Iron(III) oxide to molten iron
3CO + Fe2O3 → 2Fe (l) + 3CO2

The limestone reacts with impurities to form slag.
heat decomposes the limestone
CaCO3 → CaO + CO2
calcium oxide reacts with silicon (IV) oxide to form calcium silicate (slag)
CaO + SiO2 → CaSiO3

Question 2

What is slag used for?

Answer 2

Making roads

Making Cement