Answer
b. Burning of wood
Explanation
Chemical changes occur when a substance combines with another to form a new substance.
Physical changes are changes affecting the form of a chemical substance, but not its chemical composition.
Therefore;
a. Evaporation of gasoline is a physical change.
b. Burning of wood is a chemical change
c. Melting of paraffin wax is a physical change.
d. Freezing of water is a physical change.
