Matter has mass, volume and is made of particles. Matter is perceived by our senses. Mass is measured on a balance. You compare the object of unknown mass to an object of known mass in reality or today it is done electronically. Mass is measured by the amount of force required to change an object's direction or speed.
Chemists classify matter in order to better understand and describe it.
It takes the shape and volume of the container. It is an easily compressed fluid. A pure substance is a homogeneous form of matter which has a definite or constant composition and distinct properties. Every bit appears the same. Today we can detect one in a trillion parts of impurity of some substances.