STOKES.] 
TRIMETAPHO.SI'l I [MIC ACID. 
97 
remaining undissolved. It is best to continue the agitation for a short 
time longer in order to decompose the chlorhydriues, which are always 
formed as intermediate products. At the end of the operation nearly 
all the sodium salt has crystallized out, being almost insoluble in the 
strong salt solution; a further small amount can be recovered by mix- 
ing the solution with alcohol. After washing with 50 per cent alcohol, 
the salt is pure enough for most purposes, but may be redissolved in 
water and precipitated by gradual addition of alcohol. 
The same salt also results by decomposing triphosphonitrilic tetra- 
chlorhydrine with soda. It exists in two forms, apparently differing 
only in the amount of crystal water, the «-salt being formed at ordinary 
temperatures, the /i-salt only above 80°. 
a- Sodium trimeta/phosphimate, P3N 3 6 H;{Na 3 + 4H 2 C — The air-dried 
salt, prepared as above, gave the following figures: 
Calculated for 
P 3 N 3 6 H 3 Na 3 + 
4H 2 0. 
Found. 
1. 
2. 
p 
24.79 
11.22 
18.41 
2.94 
24.74 
11.26 
18.45 
3.05 
24. 82 
N 
Na 
18.43 
2.97 
H 
1. P:N:Na:H =3: 3.02: 3.01 :11.47. 
2. P:Na:H = 3:2.97:ll. 
It loses weight slowly in vacuo, and 3 molecules of water are given 
off on long heating at 100°. After five hours at 100° the loss was : 
r 
Calculated for 
3H 2 0. 
Found. 
, Loss 
14.38 
14.05 
This is one of the most characteristic salts of trimetaphosphimic 
icid. It forms brittle orthorhombic prisms, usually about 1-2 milli- 
aeters across, of which fig. 1 represents the most common form. 
Fig. l. 
A = co P 00 
B = Poo. 
Bull. 107 7 
