( 658 } 
This result is in contradiction with that of GeRHARDT !) who 
states that on melting Hg, (NO), nitric oxide is merely given off; 
he does not say whether he means the anhydrous or the crystallised salt. 
I think the following result an important one. During the said 
decomposition a yellow compound sublimes in the upper side and 
neck of the retort; in the lowest and consequently the hottest part 
it has fused and turned to a yellow crust, but in the neck it has 
sublimed in yellow needles. Its composition appeared to agree with 
that of a compound obtained by the moist process by Rose, *) 
GERHARDT ®) and Brooxs*) and considered by them to be basic 
mercuro-mercuric nitrate, 2 Hes O, N, O; 4 Hg O Ns Os, while it might 
also be considered as mercuro-mercuric ortho-nitrate, (Hg,) Hg, 
(NO,)2, derived from an acid Hz NO,. 
The analysis of that substance gave the following results: 
Hg, Cl, Hes Hs VEE rt ete */.NO, 
1) 0.4038 gr. 0.2054 0.1980 43.21 42.25 83.68"/, 12.98 16.32 
2) 0.6381 » 0.3139 0.3007 42.2 43.— 
8) 0.8505 » gave 23.5 cc. of N, temp. 20° press. 763 mm = 0.02685 gr. of N. or 14.08 17.94 
4) 1.1643 » » 28.5 ww» » 199 wv 757 » =0.03226 » » » » 12.31 15.68 
5) To 0.6895 gram containing 0.0085 gr. of free mercury were added 
N N 
128.7 cc. of i0 HNO,, then 157.7 cc. of KHO; after diluting to 
250 ec. the excess of KHO was determined in half of the filtrate. 
N 
Used 7.25 ec. of 10 HNO. 1310650 
The excess of mercury found in my determinations is due to 
the presence of a little free metallic mercury as shown in experi- 
ment 5. When dissolving the compound in IINO; the amount of 
both the mercurous and mercuric nitrates is consequently increased. 
Of this yellow salt a not inconsiderable quantity is formed. | 
96.4 grams of anhydrous mercurous nitrate yielded me 18.3 grams 
or nearly 19 %/, of yellow crusts and needles, also 12.2 grams or 
12.8 °/, of reddish-brown crusts formed from the at first sublimed 
and then greatly decomposed orthonitrate. It might, therefore, be 
suspected that the preparation of red Hg O according to the Dutch 
Pharmacopeea should be attended with a serious loss of mercury. In 
one experiment which I made in this direction, the loss amounted 
to: 12, Ore 
') Ann. Chem. u. Pharm. LXXII. p. 74. 
*) Poggend. Ann. LIV. p. 121. 
a) ise; 
*) Poggend. Ann. LXVI. p. 63. 
a 
bt 
ee 
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