The correct answer to the question “Which of the following is an example of a conversion from chemical energy to thermal energy?” is letter D or all of the above. In energy transformation, it is worthy to mention that it happens when there is a change of energy from one form to another form. This means that when coal is burned to boil water (A) and charcoal is burned in a barbeque pit (C) the chemical energy that is released as the coal is burned will in turn heat water and then turn it into steam.
This means that the chemical energy then causes the liquid water molecules to move faster which, in turn, increases their thermal energy. When food is digested and used to regulate body temperature (B), the chemical energy from the food is then converted into mechanical energy when the food is then broken down and absorbed by our muscles.