The zeroth law of thermodynamics states that when two systems, A and B, are in thermal equilibrium with each other, and B is in thermal equilibrium with a third system, C, then A is also in thermal equilibrium with C The ideal gas law relates the pressure and volume of a gas to the number of gas particles (atoms or molecules) and the absolute temperature of the gas

Systems are in thermal equilibrium when they have the same temperature Thermal equilibrium occurs when two bodies are in contact with each other and can freely exchange energy

thermal equilibrium — condition in which heat no longer transfers energy between two objects that are in contact; the two objects have the same temperature. zeroth law of thermodynamics — states that if two objects are in thermal equilibrium, and a third object is in thermal equilibrium with one of those objects, it is also in thermal equilibrium with the other…. ideal gas law — physical law that relates the pressure and volume of a gas to the number of gas molecules or atoms, or number of moles of gas, and the absolute temperature of the gas. pressure — force per unit area perpendicular to the force, over which the force acts.