What is activation energy

In chemistry and physics, activation energy is the energy that must be provided to compounds to result in a chemical reaction.The activation energy of a reaction is measured in joules per mole, kilojoules per mole or kilocalories per mole.

Explanation:

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.

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