Question

What happens, when a chemical bond is formed?

(a) Energy is always released.

(b) Energy is always absorbed.

(c) Both 1 and 2

(d) Either 1 or 2

Answer 1

(d) Either 1 or 2

Whether a reaction is endothermic or exothermic depends on the difference between the energy needed to break bonds and the energy released when new bonds form. 

If more heat energy is released when making the bonds than was taken in when they broke, the reaction is exothermic.