What is the theme for each of the chapters?
Well, I am not going to give you the theme for each of the chapters - rather, I will discuss the theme of the novel as a whole and then you will need to go through and trace how that theme is developed in the book through your careful reading of it.
The key theme to this novel is the capacity for evil that is within us all, and how that dark side within each of us has the power to make us do and commit heinous crimes. This is most clearly shown in the death of Piggy and the cruelties of the hunters, in particular Jack and Roger. Another key theme of the novel is what can happen to us if we are put in a place without proper law and order - it is interesting that although the children try to make and construct a kind of order through using the conch, etc, this soon breaks down to chaos and rivalry. Perhaps this novel is suggesting that if we were not living in a "civilised society" with a well established force for law and order, we could act in a similar way. All in all, this novel paints a very dark picture of society - even children, who should be "innocent", reflect this darkness in all of us and our latent tendency to lean towards savagery.