Solubility Equilibria Of Sparingly Soluble Salts

To determine the correct answer, let's explore the fundamental concept of a blast furnace and its operation in the context of temperature.

A blast furnace is a crucial component in the process of extracting iron from its ores. Its primary function is to smelt iron ores to produce iron. The temperatures required in a blast furnace can vary significantly, especially since it involves chemical reactions that reduce iron oxides to iron.

The highest temperature achieved within the blast furnace occurs at the bottom, near the tuyeres where the combustion of coke with added hot air occurs. This zone is crucial for the accurate melting of iron. The range of operational temperatures in a properly-functioning blast furnace is generally between 1600 K and 1900 K.

This leads us to analyze the given options:

• upto 5000 K: This temperature is excessively high for a blast furnace and is not possible with the current technological setup and materials.
• upto 1200 K: This is not a feasible maximum temperature for the effective operation of a blast furnace, given that the iron's melting point is higher than 1200 K.
• upto 2200 K: While higher temperatures can be achieved, 2200 K exceeds regular operational parameters for standard iron production in a blast furnace.
• upto 1900 K: This aligns with the typical highest temperatures achievable within a blast furnace, fitting standard operation requirements.

Given the standard operation of a blast furnace, the best plausible choice among the options is upto 1900 K. Therefore, the initially indicated "correct" answer, upto 1200 K, appears to be incorrect, and upto 1900 K should be the correct answer based on practical knowledge of blast furnace operation.