Of the three states of matter—solid, liquid, and gas—the state that does not have a fixed volume is gas.
- Solids have a fixed shape and fixed volume because their particles are tightly packed and fixed in place.
- Liquids have a fixed volume but no fixed shape; they take the shape of their container while maintaining the same volume.
- Gases have neither a fixed shape nor a fixed volume; they expand to fill both the shape and volume of their container and can change volume depending on pressure and temperature conditions.
