The Slope of Coexistence Curve from the Clausius-Clapeyron equation represented as dP/dT is the slope of the tangent to the coexistence curve at any point. And is denoted by dPbydT. Slope of Coexistence Curve is usually measured using the Pascal per Kelvin for Slope of Coexistence Curve. Note that the value of Slope of Coexistence Curve is always negative.