Question

What is the slag formed during the extraction of iron?

• A. $MgO$
• B. $FeSi{O}_3$
• C. $CaSi{O}_3$
• D. $MgSi{O}_3$

Answer 1

Answer: (C)

Iron is extracted from its ore, (haematite) in a blast furnace. The ore is fed into the top of the furnace along with coke and lime stone.

Carbon monoxide act as reducing agent during the reaction in blast furnace and lime stone decomposes in the hot furnace forming calcium oxide. The molten iron is then tapped from the bottom of the furnace. Further, calcium oxide react with $Si{O}_2$ to form a slag.

$CaO+Si{O}_2⟶CaSi{O}_3$

Slag can be used in making roads.