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: [[Freezing]], [[Condensing]] and [[Depositing]] are [[exothermic]] changes because they release [[energy]] when they happen. The [[material]] has less after they have happened. However, there is usually no increase in [[temperature]] because the [[material]] is usually cooled to [[State Change|change state]].
==Key Stage 4==
===Meaning===
An [[exothermic]] process is one that gives out [[energy]]. This usually causes surroundings to increase in [[temperature]].
===About Exothermic Processes===
: [[Exothermic]] [[Chemical Reaction|reactions]] usually require [[energy]] to begin. This is called the [[Activation Energy|activation energy]].
: In an [[exothermic]] process the [[Potential Energy|potential energy]] stored in the [[product]]s is less than the [[Potential Energy|potential energy]] stored in the [[reactant]]s.
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|[[File:ExothermicSketchGraphKS4.png|center|500px]]
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| style="height:20px; width:500px; text-align:center;" |To start the [[Chemical Reaction|reaction]] an [[Activation Energy|activation energy]] is needed. This is usually achieved by initially [[heating]] the [[reactant]]s. Once the [[Chemical Reaction|reaction]] starts the [[energy]] stored in the [[reactant]]s is released in the [[Chemical Reaction|chemical reaction]] making the [[material]] increase in [[temperature]]. The [[product]]s now have less [[energy]] than the [[reactant]]s.
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