Answer:
The correct answer is option B which is chemical change.
Step-by-step explanation:
- A physical change means any change in compound's physical properties like change in shape, phase or temperature during a reaction.
- A chemical change means change in chemical composition which leads to production of new compound.
- A phase change means conversion of state of a particular compound, for example from liquid to gaseous state.
- Hence in this reaction gas is produced, so its a chemical change.