Chemistry experiments in which we obtain ammonium chloride (NH4Cl) from the reaction of ammonia (NH3) with hydrochloric acid (HCl). When this reaction occurs in the air, a white cloud is observed. These are small white particles of ammonium chloride, a slightly acidic salt.
In a liquid medium, an exothermic acid-base reaction occurs, releasing heat, in which in addition to seeing bubbles due to the increase in temperature, we can see how a white cloud of ammonium chloride rises. The equivalence point of this reaction is not neutral but acidic, since ammonium chloride is an acid salt.
Ammonium chloride dissolved in water can be precipitated. To do this, we heat the solution resulting from the previous reaction to the saturation point, that is, the point at which it is no longer possible to have more solute (ammonium chloride) dissolved in water. When the saturated solution is allowed to cool, ammonium chloride begins to precipitate in the form of beautiful white star-shaped crystals.
I also show at the end of the video what the ammonium chloride crystals are like, obtained by evaporating a solution of this salt in water. Since this process is much slower than the previous one (cooling), much larger and more spectacular crystals are obtained. The images have been obtained using macro photographic lenses.

The reactants are actually solutions of gases in water respectively. Thus, hydrochloric acid is hydrogen chloride HCl dissolved in water. Ammonia, as we commonly call it (for example as a cleaning product), is actually a solution of ammonia NH3 (gas) in water. Therefore the latter is ammonium hydroxide NH4OH.

https://en.wikipedia.org/wiki/Ammoniu...
https://en.wikipedia.org/wiki/Ammonia
https://en.wikipedia.org/wiki/Hydroch...
https://en.wikipedia.org/wiki/Ammonia...
https://en.wikipedia.org/wiki/Precipi...)
https://en.wikipedia.org/wiki/Single_...