How is Elie’s arrival at Buchenwald different from his arrival at Auschwitz? How is his reaction to this place different

When Eliezer is brought to Auschwitz with his family and the other deportees from Sighet, he has no idea of the conditions that await them in this, or in any, concentration camp. There does not even seem to be any general knowledge among Hungarian Jews, who had so far been largely spared from the death camps, that the Jews of Europe are being murdered en masse. The initial shock to Elie, however, is that immediately upon arrival at Auschwitz, the men and women are separated, and he is never to see his mother and sister again, or even to hear about their specific fate. The nightmare events unfold in rapid, incomprehensible succession: the physical violence inflicted upon them, the sight of the crematoria and the piles of dead bodies, and the fact that there is no escape from this place.
Months later the arrival at Buchenwald is an entirely different situation. The prisoners, including Elie, have now seen everything, and no amount of horror is surprising any longer. But two things stand out. There is, first, the assumption by the Jewish inmates that the Germans will probably kill them soon; they have been forced to march west into the interior of Germany because the Russians are advancing from the east and taking over territory previously held by the Germans. At the same time, the knowledge that the Germans are losing the war would, under other circumstances, perhaps have aroused a feeling of hope among the prisoners. But all of them have been beaten into submission and essentially had the life drained out of them. Elie himself can feel only the growing guilt over the fact that his father's death would be the lifting of one of his own burdens. When liberation finally does come, it brings no joy. Elie's own feeling is that he has essentially become one of the living dead. When after a period of illness he is able to stand and to see his reflection in the glass, his reaction is that

From the depths of the mirror, a corpse was contemplating me.