( 2()1 ) 



Iransilioii point of' AgNO. and the tirst Iriiiisitioii point of Nil, NOj 

 falls ill I ho region where these mixtures are still [)artially li(pii(l; the 

 two lower transition points of NH^ NO^, however, are situated in the 

 region where everything has already become solidified. 



Owing to this, the deposition of AgNO., from melted mixtures rich 

 in silver takes place according to two lines which meet each other 

 at 160^; the solidification of NH^ NOj from mixtures rich in this 

 salt, also takes place along two lines which meet each other at 125''. 

 Neither transition point is modified by the mixing process, from 

 which we nmy conclude that the salts are deposited in a pure con- 

 dition and do not yield mixed crj'stals. 



From the intermediate concentrations, however, a compound 

 1) =: NH^ NOj. AgNOg is deposited with a pure melting point at 109. Ö''. 

 Its melting-point-line extends towards the Ag-side only up to 52 

 Mol. 7o, towards the NH^-side up to 30 7o Ag. Consequently, all 

 mixtures of 50 — 100 7o Ag solidify at 109"^. 6 to conglomerates of 

 D -j- Agj and all mixtures of — 50 7o Ag at 101°. 5 to conglomerates 

 of Anij -j- D. 



The latter, on further cooling, undergo a new transformation at 

 85° and 35° owing to the reversion of Am^ into Anig and then into 

 Am^. As both take place in the different mixtures at the same tem- 

 perature at which reversion of the pure AmNOg takes place, this 

 proves that no mixed crystals occur between this salt and the 

 double salt. 



If now we express the liquid mixtures Iw L we have in Fig. 1 

 the following regions. 



1 Am, + L 7 Am, -f D 3 L + Ag, 



2 Am, -fL 8 Anig-fD 4 L + Ag, 

 5 D -f L 9 Am, + D G D -{- Ag, 



The system AgNOg -\- KNO,, is simpler in so far that KNOg has 

 only got one transition temperature at 126°. 



The transition point of AgNOg again falls within the partially 

 liquid region and the solidification of the mixtures rich in Ag therefore, 

 again takes place according to two lines which meet each other at 

 1(50°. Under normal conditions, the transition point of KNO3 ^^^^^ 

 within the solid region, consequently there is only one melting point 

 line for the first form of the KNOg : K, ; in the figure this line 

 is represented only from 210" to lower temperatures; it must be 

 imagined to extend to the KNOg axis at its melting point of 338°. 



From the intermediate concentrations there is also deposited a 

 double salt D^KNOg . AgNOg but its melting-point-line only 

 extends from 



18 



Proceedings Royal Acad. Amsterdara. Vol. VI. 



