Question

sarah left a metal spoon in a pot of tomato sauce while it simmered for an hour. when she removed the spoon it had brown - orange spots and a slightly different texture. which piece of evidence best supports that a chemical change occurred?
the sauce cooled slightly after the spoon was removed.
brown - orange spots formed on the spoons surface (color change).
the spoon became wet from the sauce.
the spoon changed shape where it rested against the pot.
clear my selection

Explanation:

A chemical change involves the formation of new substances. A color change (brown - orange spots on the spoon) is a common indicator of a chemical reaction. Cooling of the sauce (a physical change related to heat transfer), the spoon becoming wet (a physical state change of water), and the spoon changing shape (a physical deformation) are all physical changes.

Answer:

Brown - orange spots formed on the spoon's surface (color change).