Investigations dealing ivith the State of Aggregation. 407 



Siir/ace Tensions of Normal Salt Solutions, jn^o = 1- 

 Sodium Salts. (Hydro) Chlorides. 



1 





1 



•032 



I 



2 





1 



•020 



II 



3 





1 



•013 



III 



4 



Sodium acetate 



1 



•004 



IV 



5 



Sodium monocMoracetate ... 



1 



•002 



V 



6 









•970 



VI 



7 



Sodium trichloracetate 







•905 



VII 



8 









•902 



VIII 



9 









•897 



IX 



10 



Sodium benzene sulphonate 







•816 



X 









XI 



Sodium chloride 



Ammonium chloride 



Monomethylamine hydrochloride 

 Trimethylamine hydrochloride .. 

 Dimethylamine hydrochloride 

 Tetraethylammonium chloride .. 



Piperidine hydrochloride 



Triethylamine hydrochloride 



Benzylamine hydrochloride 



Isoamylamine hydrochloride 



Hexylamine hydrochloride 



•032 



•027 



•017 



•0074 



•006 



•965 



•953 



•950 



•878 



•728 



■516 



Stalagmometer and pycnometer readings were taken at 15° C. 



Flocculation Capacity of Salts. 



Attempts were made to carry out the precipitation under as nearly as 

 possible constant conditions. To 2 c.c. of the sol in a series of small test- 

 tubes were added 2 c.c. of various dilutions of the salt in concentrations 

 diminishing in geometrical ratio. The salt solution was rapidly poured into 

 the sol and the mixture was then poured back into the first test-tube. 

 The limits between which precipitation took place were- then noted after 

 several hours. The finer limits were then determined by carrying out 

 the precipitation with a number of dilutions between the coarser limits, 

 and the second set of experiments were carried out at constant temperature 

 (20°), the salt solutions and sols being kept at this temperature before 

 mixing. The observations were generally made after an interval of 17 hours. 

 In the following Tables the numbers refer to the dilutions of the salts (after 

 mixing with the sols) in millimols per litre. + + + indicates complete 

 precipitation, -f- -f not quite complete precipitation, -f slight turbidity, no 

 change in sol visible to naked eye. In certain cases l^e finer limits were not 

 determined, especially when these were high, as larger amounts of costly 

 materials necessary for the experiment were not available. 



Ferric Hydroxide. 



Prepared by dilution of liqiior fcrri dialysat. B.P., diluted with seven times 

 the volume of water. 100 c.c. contained 1^33 per cent, solid, dried at 100° C. 



