NITRIC OXIDE, AND CHLORO-HYDRTC ACID. 63 



edulcorated, first with boiling water, and afterwards with diluted nitric acid. 

 The filtered solutions thus derived being saturated to excess with nitric acid, 

 were precipitated by nitrate of silver, and the chloride of silver collected on a 

 filter, washed, dried, and heated to fusion, (the proper precautions with the 

 filter being observed,) when it was weighed. The amount thus obtained was 

 •2.679 grammes, equivalent to 0.661 grammes of chlorine, or 43.32 per cent. 



18. The platinum obtained by this process was also collected on a filter, 

 Ignited and weighed, giving 0.628 grammes, or 41.16 per cent. 



19. As 41.16 platinum requires 29,55 chlorine, to form the deuto-chloride of 

 platinum, and as the quantity obtained, namely, 43.32 per cent., is nearly one 

 and a half times 29.55, it is evident that the chlorine in the salt under exami- 

 nation exists in the proportion of 3 atoms to 1 atom of platinum. 



It is obvious, also, from a previous experiment (7) that this one atom of 

 chlorine must exist in union with hydrogen as chloro-hydric acid. We, 

 therefore, show, that for each atom of deuto-chloride of platinum, the salt con- 

 tains one atom of chloro-hydric acid. 



20. Another portion of the salt, 1.2976 grammes, being introduced into a 

 weighed platinum crucible, and there mingled with an adequate quantity of car- 

 bonate of potassa, a thin stratum of which should cover the mixture, it was 

 fused, the crucible being covered. It was then edulcorated with boiling water 

 and dilute nitric acid, and was otherwise treated as in the previous experiment, 

 (17 and 18.) Thus operated upon, it furnished 2.336 grammes of chloride of 

 silver, equivalent to 0.5763 grammes of chlorine, or 44.46 ^er cent, 



21. The platinum obtained by this experiment weighed 0.549 grammes, or 

 42.36 per cent. 



22. As 42.36 of platinum requires 30.41 of chlorine to form the deuto-chlo- 

 ride, and as 44.46 per cent, is nearly one and a half times 30.41, it is not less 

 plain from this experiment than from that already recorded, (17, 18, 19,) that 

 the chlorine exists in the proportion of three atoms to one atom of the platinum 

 in the salt. 



