Which statement explains what an insulator does? An insulator cools a substance.

A] An insulator emits electromagnetic radiation.

B] An insulator warms a substance.

C] An insulator slows heat transfer.

answer: enthalpy

explanation:

for a exothermic reaction, the energy is released i.e. the energy of the products is lower than the energy of the reactants.

= enthaply

= energy of products

= energy of reactants

as , thus comes out to be negative. negative value of enthalpy shows that the reaction is exothermic.