Question

What is used in manufacturing of steel?
A) Coal
B) Coal tar
C) Coke
D) Glass

Answer 1

Hint: It is a porous, hard fuel with a grey colour. It possesses a high content of carbon along with some impurities. It is mainly prepared by heating oil or coal in the absence of air which is also called a destructive distillation process.

Complete step by step solution:
-Steel is an alloy of iron and carbon and the percent of carbon ranges to about 2 percent. Steel is widely used in infrastructure, buildings, ships, cars, electric machines etc.
-Steel is prepared through processes called Blast furnace and electric arc furnace.
- In the Blast furnace process, the raw materials are fed to a blast furnace. The blast furnace is steel a plant with cylindrical shape having a heat resistant brick lining.
- The raw materials used in the manufacturing of steel is iron ore, coke and limestone. All these are fed to the blast furnace from above and it descends down along with heating.
-Coke can be said as a form of carbon fuel as it contains high carbon content with some impurities. It is almost the pure form of carbon. And it is a very efficient fuel, it possesses the reducing effect and it reduces the iron ore. Coke is used for melting iron ore in the blast furnace.

- Coke is produced by heating coal in absence of air, all the impurities are burned off and produce pure carbon and when it is added to the blast furnace along with iron ore, the coke is consumed it produces intense heat which helps in iron ore melting. The coke doesn’t produce much smoke compared to the heat produced. Therefore it is one of the efficient fuels and is used in smelting of iron, steel etc.
Reaction of coke with iron ore (iron oxide), which reduces iron ore to elemental form.
\[FeO(solid)+C(solid)\to Fe(solid/liquid)+CO(gas)\]

So, the correct answer is “Option C”.

Note: In the manufacturing process of steel the coke, more precisely coal as coke is produced from coal have three roles – as an energy source providing the energy for the smelting process of iron ore, as a reducing agent and as a source of carbon for the final product as steel contains carbon in few percent.