Editing Chemical decomposition (section)

===Additional examples===
[[File:13. Каталитичко разложување на водород пероксид.webm|thumb|right|280px|An experiment describing catalytic decomposition of hydrogen peroxide, with {{Chem2|[[MnO2]]}} as catalyst. A concentrated hydrogen peroxide solution can be easily decomposed to water and oxygen.]]
An example of a spontaneous (''without'' addition of an external energy source) decomposition is that of [[hydrogen peroxide]] which slowly decomposes into water and oxygen <small>(see video at right</small>):

: 2 H<sub>2</sub>O<sub>2</sub> → 2 H<sub>2</sub>O + O<sub>2</sub>
This reaction is one of the exceptions to the endothermic nature of decomposition reactions.

Other reactions involving decomposition do require the input of external energy. This energy can be in the form of heat, radiation, electricity, or light. The latter being the reason some chemical compounds, such as many prescription medicines, are kept and stored in dark bottles which reduce or eliminate the possibility of light reaching them and initiating decomposition.

When heated, [[carbonate]]s will decompose. A notable exception is [[carbonic acid]], (H<sub>2</sub>CO<sub>3</sub>).<ref>{{Cite web|url=https://ibburke.wordpress.com/2011/03/27/decomposition-of-carbonic-acid/|title=Decomposition of Carbonic Acid Culminating by Elizabeth Burke|last=ibburke|date=2011-03-27|website=ibburke|access-date=2017-03-04}}</ref> Commonly seen as the "fizz" in carbonated beverages, carbonic acid will spontaneously decompose over time into [[carbon dioxide]] and water. The reaction is written as:

: H<sub>2</sub>CO<sub>3</sub> → H<sub>2</sub>O + CO<sub>2</sub>

Other carbonates will decompose when heated to produce their corresponding [[metal]] [[oxide]] and carbon dioxide.<ref>{{Cite web|url=https://Quizlet.com//|title=Synthesis and Decomposition Reactions|last=Walker|first=MS|year=2016|website=Quizlet.com/MSWalker22|series=Online Series in Organic Chemistry|language=en|type=Audio-Video Online Lecture|orig-year=Available now|access-date=2017-03-04|url-access=registration }}</ref> The following equation is an example, where ''M'' represents the given metal:

: ''M''CO<sub>3</sub> → ''M''O + CO<sub>2</sub>

A specific example is that involving [[calcium carbonate]]:
: CaCO<sub>3</sub> → CaO + CO<sub>2</sub>

Metal [[chlorate]]s also decompose when heated. In this type of decomposition reaction, a metal [[chloride]] and oxygen gas are the products. Here, again, ''M'' represents the metal:

: 2 ''M''ClO<sub>3</sub> → 2 ''M''Cl+ 3 O<sub>2</sub>

A common decomposition of a chlorate is in the reaction of [[potassium chlorate]] where oxygen is the product. This can be written as:

: 2 KClO<sub>3</sub> → 2 KCl + 3 O<sub>2</sub>