Cambridge Science – States Of Matter Practice Test

Identifying states of matter comes down to how matter behaves in terms of shape, volume, and how its particles are arranged and move. Solid objects keep a definite shape and a definite volume because their particles are tightly packed and mainly vibrate in place. Liquids have a definite volume but take the shape of their container, since their particles can slide past one another and flow. Gases have neither a definite shape nor a definite volume because their particles are far apart and move freely, filling both the space they occupy and the space around them. Other properties like color, density, or melting point aren’t universal indicators of state, since they depend on the material and conditions rather than the state itself. Similarly, mass, texture, chemical reactivity, size, weight, or odor don’t reliably reveal whether matter is a solid, liquid, or gas.