# Question Video: Determining the Correct Unit for Density given the Mass and Volume Units of a Substance Science

If a substance has a mass given in units of grams (g) and volume given in units of cubic centimeters (cm³), what unit will the density of the substance be measured in?

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### Video Transcript

If a substance has a mass given in units of grams and volume given in units of cubic centimeters, what unit will the density of the substance be measured in?

Density tells us how compact a substance is. In other words, density is how closely particles in a substance or object are packed. The air particles in a balloon are loosely packed. Air has a low density. Iron particles in an iron nail are closely packed. Iron has a high density.

We can define density as the mass of a substance per unit volume of that substance. In other words, we can calculate the density of a substance by measuring its mass then dividing the mass by its volume. Mass has many units. Mass can be measured in grams, kilograms, milligrams, and so on. There are also different units for volume. We can measure volume in centimeters cubed, millimeters cubed, meters cubed and so on.

The question says a substance has a mass measured in grams, whose symbol is lowercase g, and a volume measured in cubic centimeters, whose symbol is cm cubed. So if we take a mass value in grams and divide it by a volume value in centimeters cubed, we get a value for density in grams per centimeter cubed, or g forward slash cm cubed.

Finally, what will the unit of the density of a substance be if its mass is measured in grams and its volume is measured in cubic centimeters? The answer is grams per cubic centimeter, or g slash cm cubed.