Final answer:
Ammonia and hydrogen chloride gases undergo a neutralization reaction, in which they combine to form the salt ammonium chloride, producing a visible white smoke.
Step-by-step explanation:
When ammonia and hydrogen chloride gases are mixed, they undergo a chemical reaction known as a neutralization reaction. In this reaction, an acid and a base react to form a salt and water. In the case of ammonia (NH3) and hydrogen chloride (HCl), the reaction is as follows:
NH3(g) + HCl(g) → NH4Cl(s)
Ammonia, a base, reacts with hydrogen chloride, an acid, to produce the salt ammonium chloride. The (g) denotes that the substances are in gaseous form, and the (s) denotes that the product, ammonium chloride, is a solid. It is also worth noting that ammonia and hydrogen chloride gases produce a visible white smoke of ammonium chloride when they react.
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