In what chapter did Spitz die in The Call of the Wild?
The dog Spitz dies at the very end of Chapter 3. That is the chapter that is entitled "The Dominant Primordial Beast."
Spitz dies after a long chase and a fight with Buck. The two of them have been contending for power within the pack all through this chapter. Buck has been undermining Spitz's authority for a long time and he has finally taken the opportunity to pick a fight to the death with Spitz. They fight for a long time, and Buck finally gets Spitz down. At that point, Spitz dies just the way he killed Curly earlier in the book.