Answer
The first law of thermodynamics states that energy can only be converted and not created or destroyed.
A system can change its internal energy by releasing energy in an exothermic process or absorbing energy from the surroundings in an endothermic process.
An endothermic process represents a positive value. An exothermic process represents a negative value.
Work Step by Step
The first law of thermodynamics is also known as the Law of Conservation of Energy. This law states that energy can only be converted, not created or destroyed.
A system can only change its internal energy through an interaction with the surroundings. This may be either an endothermic process or exothermic process.
An endothermic process represents a positive value as the system is absorbing heat and therefore now has a higher internal energy. An exothermic process represents a negative value as the system is releasing heat and therefore has a lower internal energy.
