If the chemical reaction AB + CD ⟶ AD + BC releases heat, what is true of the stored bond energy of the reactants and products? The bonds do not have energy, the atoms release heat. The bond energy of the reactants is the same as the bond energy of the products. The bond energy of the reactants is lower than the bond energy of the products. The bond energy of the reactants is higher than the bond energy of the products.

The correct option is the last option

Explanation:

The chemical reaction provided in the question is a double-displacement reaction which is an exothermic reaction (which is the reason for the release of heat). An example of a double displacement reaction and exothermic reaction is the neutralization reaction illustrated below.

HCl + NaOH ⇒ NaCl + H₂O

From the law of conservation of energy, energy can neither be created nor destroyed, hence the total energy in a given system should ordinarily be the same (in the reactants and products), however when energy is released in a reaction (as in the case with an exothermic reaction), it shows there are more bond energy in the reactants than in the products and it is the excess energy that is been released into the atmosphere.

a. a primary source combines several different accounts of an event. b. a primary source generally benefits from having been written after an event.

explanation:

a:

by the combination of an unlimited number of elements