Note 45 — Chapter VI · TTHE COMPOUNDS OF NITROGEN WITH HYDROGEN AND OXYGEN
George Kamensky translation
Because if x equal the amount by weight of N2O4, its volume will = x/46, and the amount of NO2 will = 100 - x, and consequently its volume will = (100 - x)/23. But the mixture, having a density 38, will weigh 100; consequently its volume will = 100/38. Hence x/46 + (100 - x)/23 = 100/38, or x = 79·O.