NYC Chemistry Regents Exam Jan 2023
Which statement describes the changes in bonding and energy that occur when a molecule of iodine, I2, forms two separate atoms of iodine?
(1) A bond is formed as energy is absorbed.
(2) A bond is formed as energy is released.
(3) A bond is broken as energy is absorbed.
(4) A bond is broken as energy is released.
Solution: When a molecule of iodine I2 is broken into two atoms of iodine, the bond is broken. Breaking a bond means energy must be absorbed. Choice 3 is correct.