IB Chemistry SL Practice Exam Prep, Study Guide, and Practice Questions

A solid is characterized by having both a definite shape and a definite volume. This means that solids maintain their form and size regardless of the container they are in, distinguishing them from liquids and gases, which do not have a fixed shape. In solids, the particles are closely packed together in a fixed arrangement, allowing them to vibrate in place but preventing them from moving freely. This gives solids their rigid structure and distinct appearance.

The first option inaccurately describes a characteristic of gases, which are known for having neither a definite shape nor volume. The third option describes liquids, which have a definite volume but take the shape of their container. The last option refers to the compressibility of gases; solids are not easily compressed because their particles are already closely packed, leaving little space for further compression. Therefore, the accurate description of a solid is that it possesses both a definite shape and volume.