You can't get liquid iron directly from solid iron through a chemical reaction formula. The transition from solid to liquid is a physical change called melting, not a chemical change.

Here's why:

* Chemical Reactions: Involve the formation of new substances with different chemical compositions.

* Melting: Involves a change in the state of matter, but the chemical composition remains the same.

Here's how you can achieve the transition from solid iron to liquid iron:

1. Heat the solid iron: You need to provide enough heat energy to overcome the forces holding the iron atoms in a fixed, rigid structure (solid state) and allow them to move more freely (liquid state).

2. Melting Point: Iron has a melting point of 1538 °C (2800 °F). Once you reach this temperature, the iron will transition from solid to liquid.

Therefore, the transition from solid iron to liquid iron is represented by:

* Fe (s) → Fe (l) ΔH > 0

This means: Solid iron (Fe (s)) changes to liquid iron (Fe (l)) with the addition of heat energy (ΔH > 0).

Important Note: While you can't use a chemical reaction to melt iron, you can use a chemical reaction to produce iron in the first place. For example, the reduction of iron ore (Fe₂O₃) in a blast furnace produces molten iron. However, this is a complex process involving multiple chemical reactions, not just a simple conversion from solid to liquid.