Concept:A chemical change always produces a new substance, while a physical change does not.
Explanation:Chemical changes result in the formation of entirely new substances with different properties.
Physical changes only alter the state, shape, or form of matter without making a new substance.
The key difference is the formation of a new substance in a chemical change.
Options A, B, and C are not always true for chemical changes, and they may also be seen in physical changes.
Therefore, the correct distinguishing feature is the formation of a new substance.
Answer:D. A new substance is formed