urbaf2

30 CHEMISTRY AND TECHNOLOGY OF EXPLOSIVES

N 2 x

denoted by But by definition of our standard state, a 2 x = N 2 x, and therefore at any

p 2 x

concentration

FIG. 13. Activity H/Ho of HNO 3 , in solutions HNO 3 -H 2 SO 4 -H 2 O at 0°C

(Vandoni [72]).

Thermochemical measurements

On the basis of measurements of the heat generated on mixing nitric and sul-

phuric acid Gelfman [71] drew the conclusion that the two acids do not yield any

stable molecular compounds.
On the basis of similar measurements of the heat of solution of SO 3 in nitric