Which of the following is needed to produce slag during the extraction of iron in the blast furnace?
Answer Details
Limestone is needed to produce slag during the extraction of iron in the blast furnace. The blast furnace is used for extracting iron from its ore, which is a mixture mainly of iron oxide and limestone. When limestone is heated, it decomposes to form calcium oxide (CaO), which then reacts with the impurities in the ore, such as silicon dioxide (SiO2), to form slag. The slag is a waste product that floats on top of the molten iron and is removed from the furnace separately. Therefore, the correct option is B - Limestone.