Chapter 17 Heat and the first law of Thermodynamics 2)Heat(热量Q): Heat is the energ. that is transferred between a system and its environment because of a temperature difference that exists between them. (its unit is J---Joules) O Absorbing heat: Q>0; Losing heat: Q<0 o Heat is path- dependent quantity(过程量) Heat and temperature are often confused.Chapter 17 Heat and the First Law of Thermodynamics Absorbing heat：Q>0；Losing heat：Q<0 Heat is path-dependent quantity（过程量）. 2) Heat（热量Q）： Heat is the energy that is transferred between a system and its environment because of a temperature difference that exists between them.（its unit is J---Joules） Heat and temperature are often confused