State and explain the difference in base strength between phenylamine and ammonia.

Phenylamine is a weaker base than ammonia. The lone pair on the nitrogen of phenylamine is delocalised into the ring, thus making the lone pair less available to combine with hydrogen ions. Also, in order for phenylamine to act as a base, the delocalisation of the lone pair and the ring would need to be disrupted. As delocalisation increases the stability of a molecule, disrupting this system would cost energy and therefore less easily to happen.