1 Some Basic Concepts and Definitions System research region or scope a physical space a Internal energy measure of motion of microscopic particles a Temperature measure molecular mean kinetic energy Enthalpy internal energy plus displacement work Work orderly energy force multiplies displacement in the force direction Heat flow transferred heat quantity per unit time1 Some Basic Concepts and Definitions „ System research region or scope, a physical space „ Internal energy measure of motion of microscopic particles „ Temperature measure molecular mean kinetic energy „ Enthalpy internal energy plus displacement work „ Work orderly energy, force multiplies displacement in the force direction „ Heat flow transferred heat quantity per unit time