This document discusses the properties and states of matter. It defines properties as things that can be measured, and identifies shape, mass and volume as key physical properties used to determine the state of a substance. Matter can exist in three main states - solid, liquid and gas - depending on how tightly or loosely packed the particles are and how much they move. The kinetic molecular theory provides an explanation at the microscopic level, describing particles in different states as moving at different speeds and with different degrees of attraction between them. Temperature affects the kinetic energy and motion of particles.