Question

What properties distinguish solids from liquids? Liquids from gases? Solids from gases?

Short answer

Solids have a relatively hard volume and shape. Atoms and molecules are linked together in a solid. They vibrate in position but do not move.

Liquids have a fixed volume but can change shape by flowing. Atoms and molecules are weakly linked in a liquid. They wander about yet remain close to one other.

Gases have no fixed volume or shape. Atoms and molecules move freely and are far separated from one another.

Step-by-step solution

Difference between liquid and solid:

Liquids are distinguished from solids by their inability to withstand internal tangential pressures. As a result, they require the walls of a container to prevent them from flowing. Of course, this is a more accurate and complicated way of saying they tend to fill any receptacle.

Gas:

Gases will likewise flow if they are unrestrained for the same reason. They vary from liquids and solids in that their density varies greatly with pressure, whereas liquids and solids are generally incompressible and have constant density.

space:

Another explanation claims that gases expand and fill a space. However, this is merely the most usual experience and is not generally true. Gases lighter than air will rise if mixed with it, and any gas will fill any vessel if pumped or the vessel is in a vacuum.However, under some conditions, the behavior is not dissimilar to that of a liquid. A fascinating recreational physics experiment, for example, involves the use of sulfur hexafluoride in an open container. Because it is 6 times heavier than air, it likes to stay in it and even form a free surface(1), as demonstrated by making toy boats float over the gas.

Conclusion:

Gas diffusion tends to blur the interface, and the heavy gas will eventually escape and mix with air. Liquids must first evaporate, resulting in a more distinct interface.