Thermodynamics Practice Test: First Law of Thermodynamics — Flashcards

First Law of Thermodynamics topics include: Energy, enthalpy, first law for closed system, mass and energy balance.

The first law of thermodynamics states that energy cannot be created or destroyed, but can be transferred from one form to another. It is also known as the law of conservation of energy. 

The law distinguishes two main forms of energy transfer: Heat, Thermodynamic work.
The law can be stated as: Energy can neither be created nor destroyed in a system of constant mass
The amount of energy gained by the system must be exactly equal to the amount of energy lost by the surroundings 
The first law of thermodynamics relates the change in internal energy of a system to heat transfer and work done. 

The phenomenon of energy transformation can be observed in nature, such as:
Burning of wood
Generation of hydroelectric power
Swinging of a pendulum
Photosynthesis in plants