To determine the acidity or basicity of the given molecules, we need to analyze their behavior in water and their ability to donate or accept protons H+ ions .1. Ammonia NH3 : Ammonia is a weak base. When it dissolves in water, it accepts a proton H+ from water to form the ammonium ion NH4+ and hydroxide ion OH- . The reaction is as follows:NH3 + H2O NH4+ + OH-2. Hydrogen chloride HCl : HCl is a strong acid. When it dissolves in water, it donates a proton H+ to water, forming hydronium ions H3O+ and chloride ions Cl- . The reaction is as follows:HCl + H2O H3O+ + Cl-3. Water H2O : Water is amphoteric, meaning it can act as both an acid and a base. In pure water, a small number of water molecules donate a proton to another water molecule, forming hydronium ions H3O+ and hydroxide ions OH- . The reaction is as follows:2H2O H3O+ + OH-4. Carbon dioxide CO2 : CO2 is not an acid or a base by itself, but when it dissolves in water, it forms carbonic acid H2CO3 , which is a weak acid. The reaction is as follows:CO2 + H2O H2CO3Now, let's rank these molecules in order of increasing acidity and increasing basicity:Increasing basicity: CO2 < H2O < NH3Increasing acidity: NH3 < H2O < HClReasoning:- CO2 is the least basic because it does not directly form hydroxide ions OH- , but it forms a weak acid H2CO3 when dissolved in water.- H2O is more basic than CO2 because it can form hydroxide ions OH- and is amphoteric.- NH3 is the most basic because it readily accepts protons H+ and forms hydroxide ions OH- in water.- NH3 is the least acidic because it acts as a base in water.- H2O is more acidic than NH3 because it can donate protons H+ and is amphoteric.- HCl is the most acidic because it readily donates protons H+ in water, forming hydronium ions H3O+ .