Why are gases easier to compress than liquids or solids?

Gases are significantly easier to compress than liquids or solids primarily because of the vast amount of empty space between their constituent molecules.12

In the gaseous state, molecules act as independent entities that are separated by distances much larger than their own size. Because these molecules are not in constant contact, there is ample room to force them closer together by applying external pressure.123

In contrast, the condensed phases of matter—liquids and solids—consist of atoms or molecules that are already packed tightly together, often in constant contact. In these states, the constituent particles are held by strong intermolecular forces, making them much more resistant to volume changes. While some compression can occur in solids through mechanisms like bond shortening or the bending of atomic frameworks, the magnitude of this compression is far less than that observed in gases, where the primary effect of pressure is simply to reduce the large gaps between free-moving molecules.2345