Ethylene dibromide vapor pressure

It would appear from Table I that the available comparison data are just as variable as data obtained with the differential thermal analyzer. The second index of variability, the 95% confidence factor, is a measure of the expected precision for the estimated vapor pressure at 25°C. (or melting point). This includes not only the variation of the experimental points from the regression line but also the uncertainty in the slope of that line. This latter factor has a progressively greater effect as the line is extended—i.e., the further the extrapolation is carried beyond the experimental data. For ethylene dibromide, for example, there is a 95% probability of the vapor pressure lying between 12.0 and 12.8 (12.4 -r-1.032 and 12.4 X 1.032). 

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