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Explain the following type of chemical reaction, giving two examples for it: Decomposition reaction

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Question

Explain the following type of chemical reaction, giving two examples for it:

Decomposition reaction

Explain
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Solution

A reaction in which a compound breaks up due to heat application into two or more simple substances is called a decomposition reaction.

\[\ce{AB->[heat] A + B}\]
Examples:

  1. Mercuric oxide when heated, decomposes to form two elements mercury and oxygen
    \[\ce{2HgO_{(s)}->[heat] 2Hg_{(s)} + O2_{(g)}}\]
  2. CaCO3 when heated decomposes to calcium oxide and carbon dioxide.
    \[\ce{CaCO3 ->[heat] CaO + CO2}\]
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Chapter 6: Chemical Reactions - Exercise 2 [Page 86]

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Selina Concise Chemistry [English] Class 8 ICSE
Chapter 6 Chemical Reactions
Exercise 2 | Q 4.2 | Page 86

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