Which of the following statements holds true for a chemical change?

a.) in a chemical change, no new substance is formed.

b.) in a chemical change, a substance changes its phase.

c.) in a chemical change, the molecular structure of a substance changes.

d.) in a chemical change, one substance dissolves into another.

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.

"hydrogen bonding is the attraction of h atoms in the water molecule (slight + charge) to o atoms in a neighboring water molecule (slight - charge); it is a weak interatomic force. but it is still strong enough to the water molecules "stick" together."