OF ARTS AND SCIENCES. 



63 



about 4 gr. of amnionic chloride being produced in the process — 

 and precipitated with 40 cm. 1 * of magnesic chloride mixture. In ex- 

 periments (54) to (60) inclusive 40 cm. 8 of magnesic chloride mix- 

 ture from which the ammonia had been expelled by boiling were 

 added to the phosphate solution — in experiments (56), (57), (58), 

 (59), and (GO) directly, in (54) and (55) after adding enough am- 

 monia to make the solution smell distinctly of it — and ammonia 

 afterward strong in (57), (58), (59), and (60), but dilute at first in 

 (54), (55), and (56) and strong after the settling of the precipitate. 

 Solutions (59) and (60) were precipitated hot. 



M gj P,0 7 - P 2 5 found. P 2 5 required. Error. ^ro"' 



(48) 0.2880 gr. 0.1842 gr. 0.1831 gr. -fO.OOllgr. +0.60 



(49) 0.2881 gr. 0.1843 gr. 0.1831 gr. -j-0.0012 gr. -f-0.66 

 0.1846 ffr 



VII. 



(50) 0.2886 gr. 0.1846 gr. 0.1831 gr. 



(51) 0.2888 gr. 0.1847 gr. 0.1831 gr. 



(52) 0.2882 gr. 0.1844 gr. 0.1831 gr. 



(53) 0.2882 gr. 01844gr. 0.1831 gr. 



(54) 0.2865 gr. 0.1832 gr. 0.1831 gr. 



(55) 0.2870 gr. 0.1835 gr. 0.1831 gr. 

 f (56) 0.2931 gr. 0.1875 gr. 0.1875 gr. 



0.2940 gr. 0.1880 gr 



-f 0.0015 gr. +0.82 



+0.0016 gr. +0.87 



+0.0013 gr. +0.71 



+0.0013 gr. + - 71 



+0.0001 gr. +0.05 



+0.0004 gr. +0.22 



0. 0. 



+0.0005 gr. +0.27 



(57) 0.2940 gr. 0.1880 gr. 0.1875 gr. 



, (58) 0.2950 gr. 0.1887 gr. 0.1875 gr. +0.0012 gr. +0.64 



(59) 0.2983 gr. 0.1907 gr. 0.1875 gr. +0-0032 gr. +1.70 



(60) 0.3017 gr. 0.1930 gr. 0.1875 gr. +0.0055 gr. +2.93 



In experiments (61) to (66) inclusive 5 cm. 8 of strong hydrochloric 

 acid were added to 40 cm. 8 of the phosphate solution and then am- 

 monia in slight excess. Portions (61), (62), (63), and (64) were 

 precipitated with 20 cm. 8 of magnesic chloride mixture. To (65) 

 and (66) were added 20 cm. 8 of magnesic chloride mixture from which 

 the ammonia had been expelled, and afterward ammonia dilute at the 

 first and strong after the precipitate had settled. Solutions (63), 

 (64), (65), and (66) contained previous to precipitating 3 gr. of sodic 

 chloride each. 



Mg.PjOr. 



P,Oj found. P 2 5 required. 



Error. 



Per cent. 



error. 



(61) 0.0426 gr. 0.0272 gr. 0.0269 gr. +0.0003 gr. +1.11 



(62) 0.0427 gr. 0.0273 gr. 0.0269 gr. +°a)004 gr . +1.49 



(63) 0.0430 gr. 0.0275 gr. 0.0269 gr. +0.0006 gr. +2.23 

 XVL "* (64) 0.0431 gr. 0.0276 gr. 0.0269 gr. +a°°°7 gr. + 2 - 60 



(65) 0.0426 gr. 0.0272 gr. 0.0269 gr. +0.0003 gr. +1.11 



(66) 0.0426 gr. 0.0272 gr. 0.0269 gr. +0.0003 gr. +1.11 



