Use 'incongruity' to point out things that don't match up as expected. The incongruity of her punk style in the formal event caused a stir.
Pro Tip 2/3
Expectation vs Reality
It emphasizes when there's a gap between what's anticipated and what actually happens. He felt an incongruity in the quiet office which was usually buzzing with activity.
Pro Tip 3/3
Moral Contradiction
Use it to express a clash between professed principles and actual behavior. Voters noticed the incongruity between the politician's promises and his voting record.