Which statement about exothermic reactions is accurate?

as reactants form products, the potential energy decreases.

as reactants form products, the potential energy increases.

thermal energy is transferred from the product to the reacting substances.

thermal energy is transferred from the surroundings to the reacting substances.

Answer is: As reactants form products, the potential energy decreases.

There are two types of reaction:

1) Endothermic reaction (chemical reaction that absorbs more energy than it releases).

2) Exothermic reaction (chemical reaction that releases more energy than it absorbs).

For example, balanced chemical reaction:  

C₂H₅OH + 3O₂ → 2CO₂ + 3H₂O  ΔrH= -1370 kJ/mol.

This reaction is exothermic reaction (heat is released), so products have less potential energy and energy is transerred to surroundings.

a chemical reaction happens

explanation: