Question

change is a chemical change when it is accompanied by A. energy change B. formation of new substances C. change in chemical properties D. all the above​

Answer 1

Answer: The answer is option D all of the above

Explanation: A chemical reaction or chemical change is said to happen if there is (1) heat generation (2) formation of a new substance/substances from an existing substance (3) when the chemical properties of the substance changes due to an external phenomenon.

Since these are all the option available you conclude that it is all of the above which accompanies a chemical change.