A hand warmer uses the oxidation of iron as its energy source. Which statement best explains why this is suitable for a hand warmer?

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Question

A hand warmer uses the oxidation of iron as its energy source. Which statement best explains why this is suitable for a hand warmer?

Accepted Answer

B) The reaction is exothermic and releases energy to the surroundings as heat — Hand warmers rely on exothermic reactions that release energy as heat to the surroundings, warming the hand. An endothermic reaction would cool the surroundings, making it unsuitable as a hand warmer.

Answer

A) The reaction is endothermic and absorbs heat from the hand

Answer

D) The reaction is reversible and absorbs energy when reversed

Answer

B) The reaction is exothermic and releases energy to the surroundings as heat

Answer

C) The reaction requires a large activation energy to start

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