Thermal Equilibrium

The distinction between heat and temperature is subtle [blank] very important. Heat refers to the transfer of energy between systems (or bodies), whereas temperature is determined by the energy contained [blank] a singular system (or body). In other words, heat is energy, while temperature is a measure of energy. Adding heat will increase a body's temperature while removing heat will lower the temperature, thus changes [blank] temperature are the result of the presence of heat, or conversely, the lack of heat. Particles have more energy at higher temperatures, and as this energy is transferred [blank] one system to another, the fast-moving particles will collide with slower moving particles. As they collide, the faster particles will transfer some of its energy to the slower particles, and the process will continue until all the particles are operating [blank] the same rate. This is called thermal equilibrium.