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: [[Melting]], [[Evaporating]] and [[Subliming]] are [[endothermic]] changes because they need [[energy]] to happen. The [[material]] has more [[energy]] at the end than it did the beginning. However, there is usually no decrease in [[temperature]] because the [[material]] is usually being heated to [[State Change|change state]].
: [[Dissolve|Dissolving]] is an [[endothermic]] process as [[energy]] is needed to break the [[bond]]s in the [[solid]] [[solute]] to [[dissolve]]. This causes the [[solution]] to decrease in [[temperature]] while the [[solute]] is [[dissolve|dissolving]].
==Key Stage 4==
===Meaning===
An [[endothermic]] process is one takes in [[energy]]. This usually causes surroundings to decrease in [[temperature]].
===About Endothermic Processes===
====Foundation====
: [[Endothermic]] [[Chemical Reaction|reactions]] usually require [[energy]] to begin. This is called the [[Activation Energy|activation energy]].
: In an [[endothermic]] process the [[Potential Energy|potential energy]] stored in the [[reactant]]s is less than the [[Potential Energy|potential energy]] stored in the [[product]]s.
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|[[File:EndothermicSketchGraphKS4.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, since the [[energy]] stored in the [[reactant]]s less than the [[energy]] stored in the [[product]]s, this means the [[Chemical Reaction|reaction]] must take in [[energy]] from the environment which causes the surroundings to decrease in [[temperature]].
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====Higher====
: In a [[Chemical Reaction|chemical reaction]] [[energy]] is needed to break the [[Chemical Bond|chemical bonds]] holding the [[atom]]s together.
: In an [[endothermic]] [[Chemical Reaction|reaction]] [[energy]] is then [[Absorb (Physics)|absorbed]] as [[atom]]s form new [[Chemical Bond|chemical bonds]].
: This happens because there is less [[energy]] stored in the [[Chemical Bond|chemical bond]]s of the [[reactant]]s than the [[product]]s.