Zum vs für (the overlooked question)
So as the title states......i wanted to know the difference between "zum" and "für" when they come in the meaning of "for". Z.B. : Dieses Geld is fürs Essen. Dieses Geld is zum Essen. Is there a real difference between the two sentences? When zu means "for"? Another quick question: can "durch" mean "due to"?
If someone can answer these questions it would be really appreciated. Thanks in advance ^^ .