Absolute Temperature and Ideal Gas Equation

Two further ideas complete the groundwork for thermometry: first, that there is a genuinely absolute (thermodynamic) temperature scale that does not depend on the properties of mercury, resistance wire, or any other particular substance, with its own natural zero; and second, that for a fixed amount of a low-density (ideal) gas, pressure, volume and this absolute temperature are tied together by a single equation. The next two subsections devel …