Answer: Option (d) is the correct answer.
Explanation:
A property that does not bring any change in chemical composition of a substance are known as physical properties.
For example, shape, size, mass, volume, density, etc of a substance are all physical properties.
And, a property that changes chemical composition of a substance is known as chemical property.
For example, precipitation, reactivity, toxicity, combustion etc are chemical property.
So, when coal and wood were burnt then chemical change takes place because of the process of combustion.
Also, heat of combustion is being tested during the process.
Thus, we can conclude that correct match of the type of change happening is chemical change, and chemical property of heat of combustion is tested.
