9. When a piece of steel wool is burned it gains mass. Which explanation is consistent with the law of conservation of mass? A. Matter was created during the chemical reaction,
B. Heat changed into matter.
C. Matter from the air combined with the steel wool.
D. A chemical change did not take place.

the potential energy of the reactants is 200j.

from the energy diagram, the energy of the product formed is 350j; this means that, this reaction is an endothermic reaction, because it absorbs energy from its environment.

d

explanation:

alchemy hadn't scientific methods of study, appeal to mysticism and fantasy, the knowledge of chemistry and physics were modest at that time.

alchemy was - but as new rules were discovered it either changed into chemistry or it became "unscientific".