# What is "ammonium hydroxide"?

##### 1 Answer
Jun 8, 2017

Well first you will have to define your terms........

#### Explanation:

Ammonia is a colourless gas with a foul penetrating odour. It is VERY soluble in liquid water, and conc. ammonia is approx. $15 \cdot m o l \cdot {L}^{-} 1$ concentration. Fisher sells this reagent as $\text{ammonium hydroxide}$; a better name for the reagent would be simply $\text{aqueous ammonia}$, because the following acid-base reaction lies STRONGLY to the LEFT:

$N {H}_{3} \left(a q\right) + {H}_{2} O \left(l\right) r i g h t \le f t h a r p \infty n s N {H}_{4}^{+} + H {O}^{-}$

The bulk of the material in solution is still $N {H}_{3}$.

On the other hand I could take equivalent quantities of ammonia gas, and hydrogen chloride gas, and get the SALT, $\text{ammonium chloride}$, i.e.

$N {H}_{3} \left(g\right) + H C l \left(g\right) \rightarrow N {H}_{4} C l \left(s\right) \downarrow$

So the moral? $\text{ammonium hydroxide} \equiv N {H}_{4} O H \equiv N {H}_{3} \cdot {H}_{2} O$.

Aqueous ammonia, $N {H}_{3} \cdot {H}_{2} O$, has the same formulation as $N {H}_{4} O H$, i.e. $N {H}_{5} O$. Capisce?