Chemical bonds hold atoms together in molecules. to break apart the atoms in a molecule requires energy sufficient to overcome the attractive force holding the atoms together. based on this statement, when we break a chemical bond, is energy absorbed by the chemical bond or is energy released from the chemical bond?

When breaking a chemical bond, energy is absorbed by the chemical bond.

Explanation:

Chemical bonds are the forces of attraction that joins two chemical species. There are two types of chemical bonds: Strong Primary and Weak Secondary bonds.

When a chemical bond is formed between two species, it is accompanied by the release of energy. Therefore, bond formation is an exothermic process.

However, energy is always required to break a chemical bond. As energy is needed to overcome the attractive forces present between the two species. Therefore, bond dissociation is an endothermic process.

Therefore, during bond dissociation, energy is absorbed by the chemical bond.

  the   balanced   equation   for   reaction of   ca metal   with   o2 to   produce   cao   is as below

2 ca+ o2→ 2 cao2

  explanation

the reaction is   balanced     since the   number of atoms   in reactant side is   equal to   number of atoms   in   product side.   for   example   they   are 2   atom of   ca in   reactant   side   and   2   atoms of ca   in   the product side.

  the   process   is a   meet the   requirement   of   redox   reaction because :     calcium   is   oxidized   from   oxidation state 0   to 2+   while   oxygen   is reduced from   oxidation   state   0   to 2-