Question

Is ammonium hydroxide the same as concentrated ammonia?

Answer 1

You mean `NH_4OH`. And yes this is the same as concentrated ammonia.

Explanation:

Ammonia, `NH_3`, is a water like gas, that has substantial solubility in water. Once dissolved in water, it undergoes an acid base equilibrium to some extent:

`NH_3(aq) + H_2O rightleftharpoons NH_4^+ + HO^-`

The equilibrium lies strongly to the left; that is most of the ammonia, while still a water solvate, is the free base.

When we buy concentrated ammonia, I think Fisher sell it as `"ammonium hydroxide"`, i.e. `NH_4OH`; a better representation would be as `NH_3*H_2O`.

When we want to use pure ammonia as a solvent, we must buy a cylinder of ammonia gas under pressure. With a dry ice/acetone condenser, the `-78` `""^@C` temperature condenses the ammonia gas (`"boiling point ="-33.3` `""^@C`), and allows us to perform reactions in this solvent.

So to conclude ammonia gas, a pungent colourless gas, is DISTINCT from aqueous ammonia, a solution of ammonia in water. Ammonia fumes will bring tears to your eyes.

Whoops, it seems that I have already answered this question! C'est la vie.