  the ideal gas law is the equation of state of a hypothetical ideal gas. it is a good approximation to the behaviour of many gases under many conditions, although it has several limitations. it was first stated by Ãmile clapeyron in 1834 as a combination of boyle's law and charles's law.  facsimile at the bibliothÃ¨que nationale de france (pp.&nbsp;153â90). the ideal gas law is often introduced in its common form: :pv=nrt\, where p is the pressure of the gas, v is the volume of the gas, n is the amount of substance of gas (measured in moles), r is the ideal, or universal, gas constant, and t is the temperature of the gas. it can also be derived microscopically from kinetic theory, as was achieved (apparently independently) by august krÃ¶nig in 1856  facsimile at the bibliothÃ¨que nationale de france (pp.&nbsp;315â22). and rudolf clausius in 1857.  facsimile at the bibliothÃ¨que nationale de france (pp.&nbsp;353â79). ==equation== the state of an amount of gas is determined by its pressure, volume, and temperature. the modern form of the equation relates these simply in two main forms. the temperature used in the equation of state is an absolute temperature: in the si system of 
Chemistry_templates Equations_of_state Gas_laws Ideal_gas