Difference Between Molten and Liquid

The key difference between molten and liquid is that molten substances are liquids that are formed from melting a substance that is in the solid state at room temperature whereas liquid substances are already existing in the liquid state at room temperature.

Molten and liquid are two states of matter at a given temperature. Although both these states have the same properties of a typical liquid, (e.g. ability to flow) there is a difference in their method of formation. Molten substances are not actually liquids; they are formed from melting a solid substance.

1. Overview and Key Difference
2. What is Molten
3. What is Liquid
4. Side by Side Comparison – Molten vs Liquid in Tabular Form
5. Summary

What is Molten?

Molten substances are liquid state matter formed from the melting of a solid substance. This means when a substance enters the liquid state of matter from the solid state due to an external effect such as temperature, we call this liquid state the molten solid. For example, a molten salt is a salt that has been melted by increasing the temperature to obtain a liquid state salt. Therefore, this process is a phase transition of a substance. This phase transition occurs at the melting point of the solid substance.

Figure 01: Ice Cubes Melting

At the melting temperature, the bonds in the solid substance break down, and the ordering of ions and molecules tend to get a less ordered state while the solid melts to become a liquid. Generally, the molten state substances have a low viscosity as the temperature increases, with the exception of sulfur whose viscosity increases with increasing temperature.

What is Liquid?

Liquids are nearly incompressible fluids that have the ability to flow. A liquid has no particular shape, it gets the shape of the container that it is in, but the liquid retains a constant volume, and the volume is independent of pressure. Therefore, this is one phase of the four major phases of matter. E.g. solid, liquid, gas, and plasma.

Figure 02: Water – the Most Common Liquid on Earth

A liquid contains tiny particles (vibrating particles) of matter such as atoms. These particles are held together by intermolecular bonds. Most liquids resist compression, but some liquids can be compressed. Distinctively, a liquid has the property of surface tension. The most common liquid on Earth is water.

What is the Difference Between Molten and Liquid?

Molten and liquid are two states of matter at a given temperature. Although both these states have the same properties of a typical liquid, (e.g. ability to flow) they are different in the method of formation. The key difference between molten and liquid is that molten substances are liquids that are formed from melting a substance that is in the solid-state at room temperature. Meanwhile, liquids are already existing in the liquid state at room temperature.

Moreover, molten substances are made of particles that were in the solid substance while liquids are made of ions and molecules held together by intermolecular bonds.

Below infographic summarizes the difference between molten and liquid.

Summary – Molten vs Liquid

Molten and liquid are two states of matter at a given temperature. Although both these states have the same properties as for a typical liquid, (e.g. ability to flow) they are different in the method of formation. The key difference between molten and liquid is that molten substances are liquids that are formed from melting a substance that is in the solid-state at room temperature whereas liquid substances are already existing in the liquid state at room temperature.