Balancing chemical equations and the main types of reactions

A balanced chemical equation has the same number of atoms of each element on both sides, as the law of conservation of mass requires. You balance an equation by changing the coefficients in front of formulas, never the subscripts inside them, since changing a subscript would change the substance. For example, 2H2 + O2 -> 2H2O has four hydrogen atoms and two oxygen atoms on each side. Most reactions fit a few types: synthesis (A + B -> AB), decomposition (AB -> A + B), single replacement (A + BC -> AC + B), double replacement (AB + CD -> AD + CB), and combustion, where a substance reacts rapidly with oxygen; burning a hydrocarbon fuel completely produces carbon dioxide and water.

This explanation is AI-generated and can occasionally be wrong. 🚩 Report