Is silver tarnishing a physical change or a chemical change?

chemical

Explanation:

Some bronze objects tarnish to a dark brown color. Chemical properties can be identified by the changes they produce. The change of one substance into another substance is called a A piece of wood burning, an iron fence rusting, and a silver spoon tarnishing are all examples of chemical changes.

i believe you are right for all except the 3rd ( look at sqdancefan his answer is much better)