here are all the laws:
Laws of Thermodynamics
The behavior of a thermodynamic system is summarized in the laws of thermodynamics, which concisely are:
Zeroth law of thermodynamics
If A, B, C are thermodynamic systems such that A is in thermal equilibrium with B and B is in thermal equilibrium with C, then A is in thermal equilibrium with C.
The zeroth law is of importance in thermometry, because it implies the existence of temperature scales. In practice, C is a thermometer, and the zeroth law says that systems that are in thermodynamic equilibrium with each other have the same temperature. The law was actually the last of the laws to be formulated.
First law of thermodynamics
dU = δQ – δW
where dU is the infinitesimal increase in internal energy of the system, δQ is the infinitesimal heat flow into the system, and δW is the infinitesimal work done by the system.
The first law is the law of conservation of energy. The symbol δ instead of the plain d, originated in the work of German mathematician Carl Gottfried Neumann and is used to denote an inexact differential and to indicate that Q and W are path-dependent (i.e., they are not state functions). In some fields such as physical chemistry, positive work is conventionally considered work done on the system rather than by the system, and the law is expressed as dU = δQ + δW.
Second law of thermodynamics
The entropy of an isolated system never decreases: dS ≥ 0 for an isolated system. A concept related to the second law which is important in thermodynamics is that of reversibility. A process within a given isolated system is said to be reversible if throughout the process the entropy never increases (i.e. the entropy remains unchanged).
Third law of thermodynamics
S = 0 when T = 0
The third law of thermodynamics states that at the absolute zero of temperature, the entropy is zero for a perfect crystalline structure.