Silence is it awkward?

In class on Tuesday our teacher did an experiment with silence. For the first 5 minutes she did not talk or start class. At first no one reacted, but then it became awkward and people started asking what the problem was.
Our society has trained us to realized when silence is awkward. When the bell rings for class to start, it is awkward if class does not start for few minutes. After a while people start to talk just to comfort themselves. No one likes uncomfortable situations, and they try to fix those situations by talking about nonsense. Society trains us from a young age on what is appropriate and what is not. When those situations are no longer normal it creates awkwardness that no one likes to experience.