Here's a breakdown of why:
* Closely packed: The particles in a solid are very close together, with little space between them. This makes them incompressible.
* Strong attraction: The particles are held together by strong intermolecular forces (like covalent bonds or metallic bonds). These forces keep the particles in a fixed, rigid arrangement.
This close packing and strong attraction results in:
* Fixed shape: The particles cannot move freely, so the solid retains its shape.
* Fixed volume: The particles are already tightly packed, so the solid cannot be easily compressed or expanded.
In contrast:
* Liquids have weaker intermolecular forces, allowing particles to move around more freely. They take the shape of their container but maintain a fixed volume.
* Gases have very weak intermolecular forces, allowing particles to move freely and spread out to fill the entire container. They have no fixed shape or volume.
