Which statement about energy transfer in chemical reactions is accurate?

• A. Energy is transferred as heat or light, not created.
• B. Energy is created during chemical reactions.
• C. All energy changes happen only as heat.
• D. Energy transfer occurs only with catalysts.

Answer: (A)

Energy in chemical reactions is conserved and can be transferred or transformed between the system and its surroundings. When bonds break, energy is absorbed; when new bonds form, energy is released. That energy can leave as heat, appear as light, or do work on the surroundings. So the statement that energy is transferred as heat or light, not created, accurately reflects how energy moves in reactions while staying the same amount overall.

Energy isn’t created during reactions, so that part is incorrect. Not all energy changes are limited to heat—some can be released or absorbed as light, or go into or out of doing work on the surroundings. Catalysts change the rate of a reaction by lowering activation energy, not by forcing energy transfer; they don’t determine how energy moves, so the idea that energy transfer happens only with catalysts isn’t right.