Ammonia, NH3, acts as an Arrhenius base, a Brønsted-Lowry base, and a Lewis base, in aqueous solution. Write out the reaction NH3 undergoes with water and explain what properties of ammonia correspond to each of the three definitions of “base.”

Verified step by step guidance

1. Step 1: Write the chemical equation for the reaction of ammonia (NH3) with water (H2O). Ammonia accepts a proton (H+) from water, forming ammonium ion (NH4+) and hydroxide ion (OH-). The equation is: NH3 + H2O ⇌ NH4+ + OH-.
2. Step 2: Explain the Arrhenius base definition. An Arrhenius base is a substance that increases the concentration of hydroxide ions (OH-) in aqueous solution. In this reaction, NH3 increases the OH- concentration, thus acting as an Arrhenius base.
3. Step 3: Explain the Brønsted-Lowry base definition. A Brønsted-Lowry base is a substance that can accept a proton (H+). In this reaction, NH3 accepts a proton from H2O to form NH4+, demonstrating its role as a Brønsted-Lowry base.
4. Step 4: Explain the Lewis base definition. A Lewis base is a substance that can donate an electron pair. NH3 has a lone pair of electrons on the nitrogen atom, which it can donate to form a bond with a proton (H+), thus acting as a Lewis base.
5. Step 5: Summarize the properties of NH3 in the context of these definitions. NH3 acts as an Arrhenius base by increasing OH- concentration, as a Brønsted-Lowry base by accepting a proton, and as a Lewis base by donating an electron pair.