Search results
Results from the WOW.Com Content Network
In thermodynamics, a physical property is any property that is measurable, and whose value describes a state of a physical system. Thermodynamic properties are defined as characteristic features of a system, capable of specifying the system's state. Some constants, such as the ideal gas constant, R, do not describe the state of a system, and so ...
Standard state. The standard state of a material (pure substance, mixture or solution) is a reference point used to calculate its properties under different conditions. A degree sign (°) or a superscript Plimsoll symbol ( ⦵) is used to designate a thermodynamic quantity in the standard state, such as change in enthalpy (Δ H °), change in ...
Heat capacity or thermal capacity is a physical property of matter, defined as the amount of heat to be supplied to an object to produce a unit change in its temperature. [1] The SI unit of heat capacity is joule per kelvin (J/K). Heat capacity is an extensive property. The corresponding intensive property is the specific heat capacity, found ...
A phase diagram in physical chemistry, engineering, mineralogy, and materials science is a type of chart used to show conditions (pressure, temperature, etc.) at which thermodynamically distinct phases (such as solid, liquid or gaseous states) occur and coexist at equilibrium .
Extensive properties. An extensive property is a physical quantity whose value is proportional to the size of the system it describes, [8] or to the quantity of matter in the system. For example, the mass of a sample is an extensive quantity; it depends on the amount of substance. The related intensive quantity is the density which is ...
Triple point. A typical phase diagram. The solid green line applies to most substances; the dashed green line gives the anomalous behavior of water. In thermodynamics, the triple point of a substance is the temperature and pressure at which the three phases ( gas, liquid, and solid) of that substance coexist in thermodynamic equilibrium. [ 1 ...
Maxwell construction. In thermodynamic equilibrium, a necessary condition for stability is that pressure, , does not increase with volume, or molar volume, ; this is expressed mathematically as , where is the temperature. [1] This basic stability requirement, and similar ones for other conjugate pairs of variables, is violated in analytic ...
The law was actually the last of the laws to be formulated. First law of thermodynamics. d U = δ Q − δ W {\displaystyle dU=\delta Q-\delta W} where. d U {\displaystyle dU} is the infinitesimal increase in internal energy of the system, δ Q {\displaystyle \delta Q} is the infinitesimal heat flow into the system, and.