. Sulphite waste liquor and its possible utilization ... a measured amount of distilled water wasadded. 2 cc. of starch solution (1 :200) were then added and thetitration performed in the usual manner. The effect of dilutionon the end point varies directly as the dilution, as it represents theamount of standard solution required for the titration of amountsof pure water. The corrections for this effect were determined byrunning blanks with 10 cc. and 1U0 cc. of distilled water and draw-ing a line, give the correction for any dilution. In this way thefollowing data were obtained and the curve p
. Sulphite waste liquor and its possible utilization ... a measured amount of distilled water wasadded. 2 cc. of starch solution (1 :200) were then added and thetitration performed in the usual manner. The effect of dilutionon the end point varies directly as the dilution, as it represents theamount of standard solution required for the titration of amountsof pure water. The corrections for this effect were determined byrunning blanks with 10 cc. and 1U0 cc. of distilled water and draw-ing a line, give the correction for any dilution. In this way thefollowing data were obtained and the curve plotted. (Table I,Figure I.) TABLE I. cc. of H20 Cc. I2 mg. S02 added sol. Cor. cc. net per cc. liq 0 50 1O0 150 200 300 50O 1000 Blank .. 10 1000 Titrations performed at room temperature, 20° solution standardized against sodium cc. of I2 solution equivalent to mg. of S02. FIG. I. ZOO 400 600 800 cc. of Water Used 1000 Sutermeister, E. Chemistry of Pulp and Paper Making, 1920, p. courtesy of Abitibi Power and Paper Company. These experiments show that the amount of free S02 increaseswith the dilution at a decreasing rate. This would seem to indicatethat there is present some very unstable form on combination ofS02. However, the srhall increase in free S02 means that it iseither present in small amount or that an equilibrium exists be-tween the free and combined S02 and that the equilibrium condi-tions are satisfied by small concentrations of S02. When we alterthe concentration of the combined S02 by diluting, we also alterthe concentration of free S02 required for the equilibrium. If suchan equilibrium exists, the concentrations of S02 required are verysmall. B. The Effect of Temperature This effect was determined by taking 10 cc. portions, adding 50cc. of distilled water and 2 cc. of starch soluti
Size: 2528px × 989px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1920, booksubjectwoodpul, bookyear1922
