The principle that requires that a chemical equation be balanced would be the law of definite proportions. It <span>states that a given chemical compound always contains its component elements in fixed ratio (by mass) and does not depend on its source and method of preparation. Hope this answers the question.</span>
The reaction of iron sulfide (FeS) with hydrochloric acid (HCl) results in the formation of ferrous chloride (FeCl2) and hydrogen sulfide (H2S) gas. The reaction can be shown as follows:
FeS (s) + HCl(aq) ---- FeCl2(s) + H2S(g)
The bubbles indicate the formation of H2S gas which is a chemical change. The formation of bubbles indicates this change as it suggests that the reactants are combing to form products i.e. it signals a chemical reaction.
It would be B, so yeah hope that helps ya ;)
C. Include changes that alter the identity of a substance.
Answer:
amphibians
Explanation:
because frogs have to stay in water while tadpole then they come to land
