Reading Selection, Lesson 2

Density as a Characteristic Property

The density of a substance is a characteristic of that substance. Therefore, density is a property that can be used to help identify a substance. Properties used to help identify substances are called characteristic properties.

Characteristic properties are not affected by the amount or shape of a substance: A bolt made from iron will have the same characteristic properties as the hull of an iron ship or a piece of iron railing. You will encounter more characteristic properties later in the module. Perhaps you can think of some now.

Knowing the density of a substance can be useful. For example, substances with low densities can be used to make objects that fly. Based on the results you obtained in Lesson 2, do you think steel or aluminum would be better for building an airplane? Would you want to make a bike out of lead? Why or why not?