Ethylamine CH3CH2NH2 is a primary amine, while ammonia NH3 is the simplest amine. Basicity refers to the ability of a molecule to accept a proton H+ and form a conjugate acid. In the case of amines, the nitrogen atom has a lone pair of electrons that can accept a proton, forming a positively charged ammonium ion.Ethylamine is more basic than ammonia. The reason for this difference in basicity can be attributed to the inductive effect and the steric hindrance.1. Inductive effect: The presence of an alkyl group CH3CH2 in ethylamine increases the electron density around the nitrogen atom due to the electron-donating nature of the alkyl group. This makes the lone pair of electrons on the nitrogen atom more available to accept a proton, thus increasing the basicity of ethylamine compared to ammonia.Relevant chemical equations:Ethylamine + H+ CH3CH2NH3+Ammonia + H+ NH4+2. Steric hindrance: Ammonia has three hydrogen atoms attached to the nitrogen atom, while ethylamine has two hydrogen atoms and one ethyl group attached to the nitrogen atom. The ethyl group is larger and more bulky than a hydrogen atom, which reduces the steric hindrance around the nitrogen atom, making it easier for the lone pair of electrons to accept a proton.Now, let's discuss the trend in basicity of primary, secondary, and tertiary amines.Primary amines RNH2 have one alkyl group attached to the nitrogen atom, secondary amines R2NH have two alkyl groups, and tertiary amines R3N have three alkyl groups. The basicity generally follows the trend:Primary amines > Secondary amines > Tertiary aminesThe reason for this trend is a combination of inductive effect and steric hindrance.1. Inductive effect: As the number of alkyl groups increases, the electron-donating effect also increases, which should increase the basicity. However, this effect is not strong enough to overcome the steric hindrance effect.2. Steric hindrance: As the number of alkyl groups increases, the steric hindrance around the nitrogen atom also increases. This makes it more difficult for the lone pair of electrons on the nitrogen atom to accept a proton, thus decreasing the basicity.In summary, ethylamine is more basic than ammonia due to the inductive effect and reduced steric hindrance. The trend in basicity for primary, secondary, and tertiary amines is primarily influenced by the balance between the inductive effect and steric hindrance.