Inorganic Chemical Reactions can be categorized into the following broad categories: combination reactions, decomposition reactions, single displacement reactions and double displacement reactions.
2H2 + O2 --> 2H2O
In the above reaction two hydrogen molecules are reacting with one oxygen molecule to form two molecules of water. Essentially, 3 molecules of the reactant are combining to form 2 molecules of the product - so a combination reaction must have occurred.
2H2O --> 2H2 + O2
In the above reaction two water molecules decompose into two molecules of hydrogen and one molecule of oxygen. Essentially, 2 molecules of the reactant are decomposing to form 3 molecules of the product – so a decomposition reaction must have occurred.
c) Single displacement reactions are reactions where one atom or ion of a single compound is replaced by another atom/ion. Consider the following reaction:
CuO + Zn --> ZnO + Cu
In the above reaction, copper in CuO is being replaced by zinc to form ZnO and Cu.
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