Reference value standards for pH measurements in 10, 30, 50, and 70% (w/w) 2-propanol/water solvent mixtures at temperatures from 288.15 to 318.15 K

Ref. value stds., pH (RVS), for 0.05 mol kg-1 potassium hydrogen phthalate (KHPh) ref. buffer solns. in 10, 30, 50 and 70% (wt./wt.) 2-propanol/water solvent mixts. at temps. from 288.15 to 318.15 K are detd. from reversible emf. measurements of the cell Pt|H2|KHPh + KCl|AgCl|Ag|Pt. The consistency of the present results is confirmed by multilinear regression anal. of the pH values obtained for each soln. compn. and temp., allowing appropriate interpolation of pH (RVS) values within the range of the expt. The ancillary values of the std. emf. of the cell Pt|H2|HCl|AgCl|Ag|Pt are optimized through multilinear regression anal. of the available data in the literature, and the ancillary values of the first ionization const. of o-phthalic acid (H2Ph) in these solvent mixts. are evaluated from reversible emf. measurements of the cell Pt|H2|H2Ph + KHPh + KCl|AgCl|Ag|Pt