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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.
: When a [[solid]] [[melting|melts]] [[energy]] is needed to break the [[bond]]s holding the [[particle]]s in fixed positions.
: When a [[liquid]] [[evaporating|evaporates]] [[energy]] is needed to break the [[bond]]s that keep the [[particle]]s together.
: When a [[solid]] [[subliming|sublimates]] [[energy]] is needed to break the [[bond]]s holding the [[particle]]s in fixed positions and keeping the [[particle]]s together.
*[[Freezing]], [[Condensing]] and [[Depositing]] are [[exothermic]] changes because it releases [[energy]] when it happens. The [[material]] has less [[after]] it has happened.
: When a [[gas]] [[condensing|condenses]] [[energy]] is released as [[bond]]s form between adjacent [[molecule]]s to hold them together.
: When a [[liquid]] [[freezing|freezes]] [[energy]] is released as [[bond]]s form between adjacent [[molecule]]s to keep them in fixed positions.
: When a [[gas]] [[depositing|deposits]] [[energy]] is released as [[bond]]s form between adjacent [[molecule]]s to hold them together and keep them in fixed positions.
: When [[human]]s [[sweat]] the [[water]] [[evaporation|evaporates]] from the [[skin]] helping them cool down. This works because [[evaporation]] is an [[endothermic]] process so the [[sweat]] takes [[energy]] away from the [[skin]] when it [[evaporation|evaporates]].