Introduction to Matter (Book)
Properties of Matter
Mass is the amount of matter in a substance or object. Mass is commonly measured with a balance. A simple mechanical balance is shown in Figure below. It allows an object to be matched with other objects of known mass. SI units for mass are the kilogram, but for smaller masses grams are often used instead.
This balance shows one way of measuring mass. When both sides of the balance are at the same level, it means that objects in the two pans have the same mass.