Question

hey mates



types of decomposition reaction?​

Answer 1

The reactions in which one compound splits up into two or more simpler substances (elements or compounds) are called decomposition reaction.

$\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\underline{ \boxed{ \sf{ AB -> A + B}}}$

$\:\:\:\:\:\:\sf \bullet\: Where,\: AB\: is\: the \:parent \:molecule\: (reactant)$

$\:\:\:\:\:\:\sf \bullet \: A\:and \:B \:are\: the \:product \:molecules.$

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${\large{\frak{\pmb{\underline{ TYPES}}}}}$

It May Be Of Either Of Three Types -

$\underline{\underline{\maltese\:\: \textbf{\textsf{Thermal \:decomposition\: reactions}}}}$

• These are the reactions in which a compound breaks into two or more simpler substances on heating. Thus, heat is used to decompose a compound.

• This reaction is also termed as pyrolysis.

${\large{\frak{\pmb{\underline{ Example}}}}}$

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• Calcium carbonate on heating gives calcium oxide and carbon dioxide.

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$\sf \:\:\:\:\:\:{CaCO_3(s)} \:\:\:\:\overset{∆}{\longrightarrow} \atop {Calcium\: carbonate}$$\sf \:\:\:\:\:\:\:{CaO(s)} \:\:\:\:\:{+} \atop {Calcium\:oxide}$ $\sf {CO_2(g)} \:\:\:\:\atop {Carbon\:dioxide}$

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• Potassium chlorate on thermal decomposition gives potassium chloride and oxygen.

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$\sf \:\:\:\:\:\:{2KClO_3(s)} \:\:\:\:\overset{∆}{\longrightarrow} \atop {potassium\: chlorate}$$\sf \:\:\:\:\:\:\:{2KCl(s)} \:\:\:\:\:{+} \atop {potassiumum\: chloride}$ $\sf {3O_2(g)} \:\:\:\:\atop {Oxygen}$

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$\underline{\underline{\maltese\:\: \textbf{\textsf{Electrolytic \:decomposition\: reactions}}}}$

• The reaction in which a compound in aqueous solution or in the molten state is decomposed on passing electricity are called electrolytic decomposition reaction.

${\large{\frak{\pmb{\underline{ Example}}}}}$

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$\sf \:\:\:\:\:\:\:\:\:{2H_2O(l)}\:\:\:\:\: \overset{Electricity}{\longrightarrow} \atop {water}$$\sf \:\:\:\:\:\:\:{2H_2(g)} \:\:\:\:\:{+} \atop {Hydrogen}$ $\sf {O_2(g))} \:\:\:\:\atop {Oxygen}$

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$\sf \:\:\:\:\:\:\:\:\:\:\:\:\:\:{2Al_2O_3(l)}\:\:\:\:\: \overset{Electricity}{\longrightarrow} \atop {sodium \:chloride}$$\sf \:\:\:\:\:\:\:{4Al(l)} \:\:\:\:\:{+} \atop {Aluminium}$ $\sf {3O_2(g))} \:\:\:\:\atop {Oxygen}$

$\underline{\underline{\maltese\:\: \textbf{\textsf{Photochemical \:decomposition\: reactions}}}}$

• When a compound is decomposed by light, it is called photochemical decomposition reaction or photolysis.

${\large{\frak{\pmb{\underline{ Example}}}}}$

• Silver chloride, on exposure to light, is decomposed to give silver and chlorine.

$\sf \:\:\:\:\:\:\:\:\:\:\:\:{2AgCl(s)}\:\:\:\:\: \overset{Sunlight}{\longrightarrow} \atop {silver \:chloride}$$\sf \:\:\:\:\:\:\:{2Ag(s)} \:\:\:\:\:{+} \atop {Silver}$ $\sf {Cl_2(g))} \:\:\:\:\atop {chlorine}$

• Hypochlorous acid decompose in presence of light to give hydrochloric acid and oxygen.

$\sf \:\:\:\:\:\:\:\:\:\:\:\:\:\:\:{2HOCl(aq)}\:\:\:\: \overset{Sunlight}{\longrightarrow} \atop {Hydrochlorous\:acid}$$\sf \:\:\:\:\:\:\:{2HCl(aq)} \:\:\:\:\:{+} \atop {Hydrochloric\:acid}$ $\sf {O_2(g))} \:\:\:\:\atop {Oxygen}$

Answer 2

Explanation:

Decomposition reactions can be classified into three types: Thermal decomposition reaction. Electrolytic decomposition reaction. Photo decomposition reaction.