Which statement of the following is correct?
A. When one substance is converted into another, there is not always an associated conversion of one form of energy into another.
B. The chemical energy of a substance is due to the potential energy stored in the arrangements of its atoms.
C. Closed systems are systems that do not exchange energy and matter with their surroundings.
D. Generally, the actual values of initial internal energy and final internal energy for any system can be determined of practical interest.