Question

Which of the following Will result in a chemical change
A. Drying wood in the shed
B. Burning coal in a furnace
C. Melting ice to obtain water
D. Evaporating alcohol into vapor

Answer 1

Burning coal because when you burn something you are reacting it with oxygen.

Answer 2

Answer:

A chemical change is the change in which a new substance is formed.

Explanation:

A physical change occurs with a change in its physical state for example melting of solid ice to liquid water or condensation of water vapour to liquid water

So, Burning Coal in a furnace will be the answer as  $CO_2$ is the new substance is produced.

All other process like drying, melting of ice ,evaporation of alcohol are examples of physical change as there is no new substance formed in it. We see only a change in the physical state of the substance.