Which term refers to the measure of mass per volume?

The term that refers to the measure of mass per unit volume is density. Density is a physical property of materials and is defined mathematically as the mass of an object divided by its volume (density = mass/volume). This relationship provides insight into how compact or spread out the matter within an object is.

Understanding density is crucial in various fields of engineering and design because it influences the selection of materials based on their weight and the space they occupy. For example, materials with high density may be preferred for structural applications requiring strength, while low-density materials might be chosen for insulation or lightweight structures.

The other terms do not specifically measure the mass per volume. Volume refers solely to the three-dimensional space an object occupies, mass is the measure of the amount of matter in an object, and concentration typically refers to the amount of a substance in a certain volume of a solution, which is a different concept. Thus, density is the correct and relevant terminology in this context.