In short
A chemical reaction is a process in which one or more substances, the reactants, change into one or more new substances, the products, by breaking and forming chemical bonds.
It is written as an equation, , and the equation must be balanced. The main types are combination (two or more substances join), decomposition (one substance splits), displacement (a more reactive element replaces a less reactive one), double displacement (ions swap partners) and redox (electrons are transferred).
is a combination reaction. There are four hydrogen atoms and two oxygen atoms on each side, so the equation is balanced.
Also searched as: chemical reactions, science reaction, types of chemical reactions.
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