alleryStart learning →What happens to energy when a chemical bond is formed?
AEnergy is absorbed, an endothermic step
BEnergy is released, an exothermic step
CEnergy is unchanged during the process
DEnergy is destroyed inside the new bond
Answer & Solution
Correct answer: B. Energy is released, an exothermic step
1. Breaking a bond needs energy put in, so bond breaking is endothermic.
2. Bond forming is the reverse of bond breaking, so it must give energy out and is exothermic.
3. The two amounts are equal in size and opposite in sign for the same bond.
4. Energy is never destroyed, so the last option would break the conservation of energy.
_Source: OpenStax Chemistry (CC BY 4.0), Ch 7 "Chemical Bonding and Molecular Geometry", section Formation of Covalent Bonds_
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