Whats a thermodynamic temperature?
A thermodynamic temperature scale is consistent with all laws of thermodynamics. As the “true” temperature scale, the thermodynamic temperature scale is independent of the properties of any particular substance. This requirement is important for high-accuracy temperature measurements. For example, the temperatures read from a mercury thermometer and an alcohol thermometer don’t quite agree with each other. The trouble is that the rate at which liquid volume changes with temperature isn’t a constant- at higher temperatures, the liquids expand more per degree temperature rise than they do at lower temperatures. The degree marks would have to be placed farther apart on the barrel of the thermometer for higher temperatures than for lower ones. The degree spacing would also depend on the liquid used to fill the thermometer.
