Which of these is used in extraction of metals?

Question

Accepted Answer

Explanation:

1. **Coke (Option 1):** Coke is the correct answer because it is a crucial material used in the extraction of metals, particularly in the process of smelting iron ore in a blast furnace. Coke serves as both a fuel and a reducing agent. It provides the necessary heat to melt the ore and facilitates the reduction of metal oxides to pure metal by removing oxygen. The carbon in coke reacts with oxygen to form carbon monoxide, which then reduces the metal oxides to metal. This process is essential in the production of iron and steel, making coke indispensable in metal extraction.

2. **Coal gas (Option 2):** Coal gas is not used in the extraction of metals. It is a byproduct of the coal carbonization process and is primarily used as a fuel for heating and lighting. While it can be used as an energy source, it does not play a direct role in the chemical reduction of metal ores, which is necessary for metal extraction.

3. **Coaltar (Option 3):** Coaltar is a byproduct obtained during the destructive distillation of coal. It is not used in the extraction of metals. Instead, coaltar is primarily used in the production of chemicals, dyes, and pharmaceuticals. It does not have the properties required to act as a reducing agent or fuel in metal extraction processes.

4. **Petroleum (Option 4):** Petroleum is a complex mixture of hydrocarbons and is primarily used as a source of fuel and raw materials for the petrochemical industry. It is not used in the extraction of metals. The processes involved in metal extraction require specific reducing agents and fuels, such as coke, which petroleum does not provide.

In summary, coke is the correct choice because it is specifically used in the extraction of metals due to its properties as a reducing agent and fuel, which are essential for the smelting process. The other options do not fulfill these roles in metal extraction.