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Do chemical changes involve energy?

Answer 1

Indeed.

Both the creation of new chemical bonds and the breaking of preexisting ones require energy.

Think about the following reaction to understand how chemical changes involve the breaking of existing bonds and the creation of new ones.

2#H_2# + #O_2# -> 2#H_2O#

Energy is required to break the double covalent bonds in the O=O molecules and the single covalent bonds in the H-H molecules during the reaction.

New single bonds are created between the H and O atoms during the formation of water (H-O-H), which releases energy.

There are many videos on YouTube that demonstrate this reaction, but in the end, a lot of energy will be released because the energy needed to break the bonds between the H-H and O=O molecules is less than the energy released during the formation of water.

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Answer 2

Luna Chen

Yes, energy plays a role in chemical changes.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.