Question

hydrogen gas (h2) and water (h2o) are both molecules but are not both compounds. draw a model to help support your answer.

Answer 1

The answer is the atoms of the reactants have combined to form a new substance. Every product of a chemical equation has to be a new substance. If their is no new substance then, a chemical change never occurred and there is no chemical equation. The new substance never has the same properties as the reactants. That's why they call it a "new" substance. Also, the atoms are the ones that combine. They are not mixed