Both HCl and Ammonium Hydroxide are corrosive and toxic. Avoid exposure.
Chemicals and Solutions:
Conc. HCl (hydrochloric acid)
Conc. NH4OH (aqueous ammonia)
Special 250 ml Erlenmeyer flasks with 34/35 and special stopper with fritted glass tips (2)
Remove the fritted glass stopper from the HCl flask and “waft” the tip near the opening of the ammonia flask. A white cloud of ammonium chloride will form.