In To Kill a Mockingbird, what is the mood of Chapter 9

The mood of Chapter Nine is one of tension.

My fists were clenched and I was ready to let fly. Atticus had promised me he would wear me out if he ever heard of me fighting any more; I was far too old and too big for such childish things, and the sooner I learned to hold in, the better off everybody would be. I soon forgot. Cecil Jacobs made me forget.

“Because I could never ask you to mind me again. Scout, simply by the nature of the work, every lawyer gets at least one case in his lifetime that affects him personally. This one’s mine, I guess. You might hear some ugly talk about it at school, but do one thing for me if you will: you just hold your head high and keep those fists down. No matter what anybody says to you, don’t you let ‘em get your goat. Try fighting with your head for a change… it’s a good one, even if it does resist learning.”

I drew a bead on him, remembered what Atticus had said, then dropped my fists and walked away, “Scout’s a cow—ward!” ringing in my ears. It was the first time I ever walked away from a fight.