How is Eliza's behavior at the ball different from her behavior at the "at-home,"

In this act we witness the transformation of Liza the flower-girl into Eliza the society lady. The change caused by repackaging her in new clothing and providing her with a new accent is so complete that she goes unrecognized by people who have seen her in her former state. Even the rough content of her conversation does not reveal her class, despite the concerns of the people who know to look out for such content.