When covalent bonds form between two atoms, both atoms' outer shells a. become ionized. b. are full of electrons. c. require additional electrons to become full. d. will easily give up electrons in order to become more stable.

a. energy is absorbed in the reaction.

if in a given reaction the energy of products is greater than the energy of reactants it means that reaction is endothermic and during the reaction, the energy is absorbed by reactants. in an endothermic reaction, the products have more stored chemical energy than the reactants. and in this reaction the reactants are more stable than products before the compounds with less energy are always more stable.