Ammonia and the Three Methylamines

Abstract

The conventional statement is: “For a weak base such as ammonia NH₄OH, BOH = B⁺ + OH⁻,

$$\frac{{[B^ + ][OH^ - ]}} {{[BOH]}}\frac{{a^2 }} {{(1 - a)V}} = K_b$$

where K _b is the dissociation constant of the base.” The so-called “0.88 ammonia” is about 18.0 M, 31.3 m, and contains about 0.564 mole per mole (H₂O) of water at 12°C. At 0°C, $x_{NH_3 }$ is 0.953 for $p_{NH_3 }$, and this corresponds to 52.9 m and should, in accordance with the conventional statement, be looked upon as almost “pure NH₄OH.”