= Linearized plot of Boyle's law
{title2=$p=C(1/V)$}
A <linearized plot of Boyle's law> uses $x=1/V$ as its horizontal coordinate. Then <absolute pressure> satisfies $p=Cx$: the <slope> is $C=nRT$, and the ideal intercept is zero. In the figure, $(V,p)=(100,100)$ and $(50,200)$ in $\mathrm{cm^3}$ and $\mathrm{kPa}$ become $(x,p)=(0.010,100)$ and $(0.020,200)$ in $\mathrm{cm^{-3}}$ and $\mathrm{kPa}$. Both give <slope> $10\,000\,\mathrm{kPa\,cm^3}$. The Vernier experiment includes this reciprocal-<volume (thermodynamics)> graph as its extension.<Chemistry with Vernier/6 Boyle's Law: Pressure-Volume Relationship in Gases>[Experiment 6, printed p. 6–4, Extension steps 1–2: pressure versus reciprocal total volume and linear fitting]{ref}
At constant <atmospheric pressure>, <gauge pressure> instead obeys $p_g=Cx-p_{\rm atm}$, with the same <slope> and a negative intercept. A nonzero fitted intercept in an intended <absolute pressure> plot can indicate <sensor bias> or an incorrect <volume (thermodynamics)> correction, but is not by itself a unique diagnosis. The origin is a mathematical extrapolation to infinite <volume (thermodynamics)> and zero <absolute pressure>, rather than an additional measured state.
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