Consider the following statements: Coke is one of the materials of the charge added to blast furnace for the production of steel/iron. Its function is to I. act as a reducing agent. II. remove silica associated with the iron ore. III. function as fuel, to supply heat. IV. act as an oxidizing agent. Of these statements:
- AI and II are correct
- BII and IV are correct
- CI and III are correctCorrect
- DIII and IV are correct
Explanation
The correct answer is C because coke serves two primary roles in a blast furnace. First, it acts as a fuel by burning to provide the high temperatures required for the smelting process, which justifies statement III. Second, it acts as a reducing agent. When coke burns, it produces carbon monoxide, which reacts with the iron oxide in the ore to strip away the oxygen and leave behind metallic iron, which justifies statement I.
Regarding the other statements, statement II is incorrect because the removal of silica is the primary function of limestone, which acts as a flux, not coke. Statement IV is incorrect because coke is used to remove oxygen, which is a reduction process, whereas an oxidizing agent would add oxygen. Therefore, only statements I and III accurately describe the functions of coke.
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