Question

AP Chem Help!
A process results in the formation of a gas as energy is absorbed. Which statement correctly classifies the change that is taking place?

A.The formation of a gas is evidence that a chemical change must have occurred.
B. The change is a physical change whenever the formation of a new substance is not specified.
C.The absorption of energy can only occur during a chemical change.
D.The change is ambiguous, because the evidence can result from either a chemical or a physical change.