2. Solids In a solid the molecules are closely bound to one another by molecular forces. A solid holds its shape and the volume of a solid is fixed by the shape of the solid.
3. Liquids In a liquid the molecular forces are weaker than in a solid. A liquid will take the shape of its container with a free surface in a gravitational field. In microgravity, a liquid forms a ball inside a free surface. Regardless of gravity, a liquid has a fixed volume.
4. Gases Gases are often invisible. Gases do not keep their shape or always take up the same amount of space. They spread out and change their shape and volume to fill up whatever container they are in. Gases can be squashed. Heating a liquid can turn it into a gas. This is called evaporation. Cooling a gas can turn it into a liquid. This is called condensation. A gas can turn directly into a solid with out becoming a liquid. This is called solidification.
5. Thank You For Watching Our Slideshow on The Three States of Matter