Apparent equivalent weight

Apparent equivalent weight deterrnined by titration with hydrochloric acid. APHA color determined by ASTM D1209, platinum—cobalt method. 

Apparent equivalent weight can be deterrnined by titration with hydrochloric acid using a bromocresol green indicator. Calculations give the equivalent weight of total amines and are not specific for the mono-, di- or tri alkan olamines. 

Apparent equivalent weight deteimined by titration with hydrochloric acid. 

In column 3 this association colloid has been charsLCterized by its apparent equivalent weight (p. 273, 1 f) and it then shows quite the same behaviour as the other substances which are macromolecular colloids (p. 188). 

The apparent equivalent weight is necessarily higher than the true equivalent Weight, the frequence of occurrence of ionised groups along the chain molecule becomit smaller. 

The said apparent equivalent weights play a great part in complex coacervation of oppositely charged colloids, and explains for instance the shift in optimal mixing ratios by altering the pH (see p. 322, 6b and p. 359, chapter X, 2i). 

Further the magnitude of the apparent equivalent weights of both colloids is here of great importance, the interaction being the more intense, the lower the apparent equivalent weight (see p. 374). 

Proteins taking part in the formation of tricomplex colloid systems (see p. 415), act however preferably as amphoions. Therefore the above no longer applies here, for at the most favourable pH, namely the the apparent equivalent weight is... 

This apparent equivalent weight plays a great part a) in determining the spread of cations in the reversal of charge spectrum ( 21, p. 295) b) in the extent of the antagonism CaCIg — NaCl ( 5 b, p. 314-315) c) in complex flocculation or complex coacervation with positive protein sols (see p. 374 Ch. X 2r). 

We see further, that the antagonism becomes more and more pronounced as the value of Q increases. Combining these facts with the role of the reciprocal hexol number (or apparent equivalent weight) in determining the spread of cations in the... 

Both apparent equivalent weights are functions of pH and to get an impression of the relative change of these equivalent weights with pH, we can use the electrophoresis pH curves of both colloids. See Fig. 44. 

At the L E. P, of the gelatin used (pH 4.82), the electrophoretic velocity being zero, the apparent equivalent weight of gelatin is infinite. That of gum arabic has a finite value, not being very different from its value at pH 6. 

If the pH is decreased further the changes in apparent equivalent weights proceed further in the directions indicated (that of gelatin decreases, that of gum... 

The particular form of curves similar to that of Fig. 43 must in principle be calculable from data on the apparent equivalent weight (see p. 273) of both colloids involved. 

It can be foreseen that such curves will not necessarily always show exactly the same shape, for this will depend on the variation of the apparent equivalent weights with pH. 

Takii into account that the reciprocal germanin number is 10—15% smaller than the equivalent weight (see 1 c, p. 269) the (apparent) equivalent weight of clupein at this pH would amount to about 290— 307. 

According as the pH is chosen lower, the (apparent) equivalent weight of the gelatin decreases and that of the gum arabic increases (decrease of the dissociation of the COOH group) and thus the mixing proportion of the optimum coacervation expressed in % A also increases. 

The curves in Fig. 2a and 4a must thus begin at the isoelectric point of the gelatin (at this point the apparent equivalent weight of the gelatin is infinite and... 

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