842 
THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. 
[April 20, 1872. 
dHjajjta for Stifocnis. 
CHEMICAL NOTES TO THE PHARMACOPOEIA. 
BY WILLIAM A. TILDEN, D.SC. LOND. 
DEMONSTRATOR OF PRACTICAL CHEMISTRY TO THE 
PHARMACEUTICAL SOCIETY. 
Sod.e Nitras, NaN0 3 .— [§ A native salt, puri¬ 
fied by crystallization from water.] Imported in 
large quantity from Peru and Chili. It is sometimes 
called cubic nitre, but the crystals are obtuse rhom- 
boliedra, of the same form as calc-spar. It gives the 
usual reactions of nitrates. [See Acidum Nitri- 
cum.] It should be free from chloride and sulphate, 
.and, therefore, give no precipitate with nitrate of 
silver and chloride of barium. Chloride especially 
should not be present in any notable proportion, or 
nitric acid prepared from the salt will be contami¬ 
nated with hydrochloric acid. 
Soda: Phosphas, Na 2 HP0 4 .12H 2 0.—Bone-asli 
is digested with sulphuric acid, and the soluble su¬ 
perphosphate which is formed, separated from the 
sulphate by treating the mass with water. 
€a 3 (P0 4 L + 2H 2 S 0 4 = CaH 4 (P0 4 ) 2 + 2 Ca S 0 4 . 
The liquid is filtered off, evaporated, and left at 
rest to deposit sulphate of calcium. It is then boiled 
with carbonate of sodium till the precipitate ceases 
do form, and the liquid has acquired a feeble alka¬ 
line reaction. 
Ca IP 4 (P0 4 B + Na 2 C0 3 
= CaHP0 4 + Na 2 HP0 4 + C0 2 + H 2 0. 
[§ Heated with solution of potash, no odour of 
ammonia is evolved, and no precipitate is formed.] 
Sulphate of ammonium and iron salts are thus 
shown to be absent. [§ 50 grains (=3*240 grams) of 
it dissolved in distilled water, and acidulated with 
hydrochloric acid, give by the addition of chloride of 
barium a white precipitate, which, when it has been 
washed and dried, weighs 36*18 grains (=2*344 
grams).] * 
Na„S0 4 .10H 2 O + BaCL 
Sulphate of Sodium. 
322 
= BaSO 4 . -j- 10H 2 O -f- 2NaCl 
Sulphate of Barium. 
233 
322 : 233 : : 50 : 3GT8 
or 3-24 : 2*344 
Soda: Valerianas. NaC 5 H 9 0 2 . 
The Pharmacopoeia directs fusel oil to be dis¬ 
tilled with a solution of bichromate of potassium 
mixed with sulphuric acid, and the valerianic acid 
which collects in the receiver to be neutralized by 
solution of soda. 
The reaction which takes place when amylic 
alcohol is submitted to oxidation has already been 
adverted to (Alcohol Amylicum), and some objec¬ 
tions to the use of crude fusel oil pointed out. 
When pure amylic alcohol is used, and chromic acid 
the oxidant employed, the changes which occur are 
shown in the following equations:— 
The precipitated mono-calcic phosphate is filtered 
off. and the sodium salt ciystallized from the filtrate. 
[§ In transparent colourless rhombic prisms, ter¬ 
minated by four converging planes, efflorescent.] 
Phosphate of sodium crystallizes in another form 
with seven molecules of water. These two com¬ 
pounds are isomorphous with the corresponding 
arseniates. [§ Its solution has a faintly alkaline re¬ 
action ; it gives a yellow precipitate with nitrate of 
silver, the resulting fluid acquiring an acid reac¬ 
tion.] 
Na 2 HP0 4 -f 3 AgN 0 3 
= Ag 3 P0 4 + 2NaN 0 3 + HN0 3 . 
[§ Heated to dull redness it loses 03 per cent, of 
Its weight, leaving a residue which, when dissolved 
In water, gives with chloride of barium a precipitate 
almost entirely soluble in diluted nitric acid.] 
2 [Na 2 HP0 4 ] — H 2 0 = Na 4 P 2 0 7 . 
llisodic Ortho- Pyrophosphate, 
phosphate. 
£See also Acidum Phosphoricum.] 
'Soda: Sulphas, Na 2 SO 4 10H 2 O.— [May be ob¬ 
tained from the residue left in the manufacture of 
hydrochloric acid by neutralizing it with carbonate 
of soda, and crystallizing from solution in water.] 
2[NaHS0 4 ] + Na 2 C0 3 
Acid Sulphate of Carbonate of 
Sodium. Sodium. 
= 2[Na 2 SOJ + H 2 0.C0 2 . 
Sulphate of Sodium. Carbonic Acid. 
[§ In transparent oblique prisms, has a salt and 
hitter taste; effloresces on exposure to the air; so¬ 
luble in water, insoluble in spirit. Exposed to heat 
in a porcelain crucible, it loses 55*9 per cent, of 
water.] 
Na 2 SO 4 10H 2 O (=322) loses 10 H 2 O(=180) 
and 322 : 180 : : 100 : 55*9. 
K 2 Cr 2 0 7 
4H 2 S0 4 
Red Chromate of Potassium 
and Sulphuric Acid. 
+ 
3 [0,H„H0] 
Amylic Alcohol. 
- o 
K 2 Cr 2 (S0 4 U 
4 PI 2 0 
Potassio-chromic sulphate 
and Water. 
+ 3 [C 5 H, O H O] 
Valerianic Acid. 
The nascent valerianic acid acts on a portion of the 
amylic alcohol as j r et unattacked, and converts it into 
a compound ether, the amyl valerate. 
C 6 H n HO + C 5 H 9 OHO 
Amylic Alcohol. Valeric Acid. 
= c 5 h 9 oc 5 h„o + h 2 o. 
Valerate of Amyl. Water. 
This is afterwards decomposed, when the distillate 
is neutralized by soda— 
C 6 H 9 OHO + NaHO 
Valeric Acid. Sodium Hydrate. 
= C 5 H 9 ONaO + H 2 0 
Valerate of Sodium. Water. 
C 5 H 9 OC 6 H h O + NaHO 
Valerate of Amyl. Sodium Hydrate. 
= C 5 H 9 ONaO + C 5 HjjHO. 
Valerate of Sodium. Amylic Alcohol. 
[§ In dry white masses without alkaline reaction, 
entirely soluble in rectified spirit, and giving out a 
powerful odour of valerian on the addition of diluted 
sulphuric acid.] 
I These compounds derive their name from that of 
the Valeriana officinalis, from which plant the acid 
was originally obtained. The odour of the plant is, 
however, very different from that of valerianic acid, 
* The number 72 - 2 in the B.P. is a mistake. 
