Work (thermodynamics) of the energy went out as heat, and how much as work. This can be summarized by saying that heat and work are not state functions of the system. This is in contrast to classical mechanics, where net work exerted by a particle is a state function. Pressure–volume work (or "PV" work) occurs when the volume of a system changes. "PV" work is often measured in units of litre-atmospheres where = . However, the litre-atmosphere is not a recognised unit in the SI system of units, which measures P in Pascal (Pa), V in m, and PV in Joule (J),
Strain energy in the form of mechanical work. For example, the heat of combustion of cyclopropane (696 kJ/mol) is higher than that of propane (657 kJ/mol) for each additional CH unit. Compounds with unusually large strain energy include tetrahedranes, propellanes, cubane-type clusters, fenestranes and cyclophanes. More on strain energy The work done in deforming the materials or The potential energy of the molecules due to their displacement from their mean position is called strain energy by tajamul Strain energy In physics, strain energy is the energy stored by a system undergoing deformation. For linearly elastic materials, strain energy is: formula_1 where σ