Types of Chemical Reactions Chemistry Tutorial
- A chemical change, or chemical reaction, involves the formation of at least one new substance.
- In a chemical reaction, atoms from reactants are rearranged to form products.
- There are many ways to classify chemical reactions.(1)
In this tutorial we will use the following classifications:
(a) synthesis reactions (or direct combination reactions)
(b) decomposition reactions
(c) single replacement reactions (or single displacement reactions)
(d) double replacement reactions (or double displacement reactions)
- In a synthesis reaction, elements or compounds react to produce a new compound.
- In a decomposition reaction a compound is broken up into smaller compounds or elements.
Decomposition reactions can be further classified as:
(i) thermal decomposition (decomposition when heated)
(ii) electrolytic decomposition (decomposition when an electric current is passed through)
- In a single replacement reaction one element replaces (or displaces) another element in a compound.
- In a double replacement reaction, atoms or ions in both reacting compounds are exchanged to form products.
Double replacement reactions may be further classified as:
(i) precipitation reactions
(ii) neutralisation reactions
(iii) double decomposition reactions