JEE Advanced · 2022 · 28 Aug 2022 · Paper 2 · General Principles and Processes of Isolation of Metals

Option (A): Limestone (${\mathrm{CaCO}}_3$) decomposes to $\mathrm{CaO}$, which reacts with silicate impurities (${\mathrm{SiO}}_2$) to form slag (${\mathrm{CaSiO}}_3$). Correct.

Option (B): Pig iron produced in the blast furnace contains approximately 4% carbon along with other impurities. Correct.

Option (C): In the blast furnace, coke reacts with ${\mathrm{CO}}_2$ to regenerate CO:

Correct.

Option (D): The exhaust gases from a blast furnace consist mainly of ${\mathrm{CO}}_2$, CO, and ${\mathrm{N}}_2$, not ${\mathrm{NO}}_2$. Incorrect.