How is density different from mass and volume?
Mass of a substance is a measure of the amount of matter contained in that substance. It is an extensive property and varies with changes in the quantity of a substance. In simple terms, higher quantity of a substance has more mass as compared to lower quantity of the same substance. It is measured in kilograms or grams, etc.
Volume is a measure of space occupied by a substance. It is also an extensive property of matter. It is measured in liters, milliliters, etc.
Density of a substance is the ratio of its mass to its volume, that is
Density = mass/volume
It is an intensive property of matter. In other words, increase in the quantity of a substance does not increase its density. It is measured in kg per cubic meter or grams per milliliters, etc.
Hope this helps.