Final answer:
Ammonia acts as a base by accepting a proton from water, forming ammonium and hydroxide ions. This reaction is represented by the word equation: Ammonia + Water → Ammonium ions + Hydroxide ions.
Step-by-step explanation:
To represent ammonia behaving as a base, we can write a word equation that depicts its reaction with water. The word equation is:
Ammonia + Water → Ammonium ions + Hydroxide ions.
This shows that ammonia (NH3) accepts a proton (H+) from water (H2O), forming ammonium ions (NH4+) and hydroxide ions (OH-), demonstrating its basic behavior. The reaction in formula form is: NH3(aq) + H2O(l) → NH4+(aq) + OH-(aq). This process illustrates that water acts as an acid in this context, donating a proton to the ammonia. The conjugate acid-base pairs are NH4+/NH3 for ammonia and H2O/OH- for water.
Although ammonia is a weak base, it still undergoes this acid-base reaction, showing that only a small fraction dissociates into ammonium and hydroxide ions in water.