Science explained

What happens in a chemical reaction

Chemical reactions rearrange atoms by breaking and forming bonds while conserving the number of each kind of atom.

ChemistryReactions

Editorial review: August 12, 2026 · Julian E. Marston

Reactants become products

The identities of substances change because atoms are connected differently.

Energy can be absorbed or released

Bond changes alter how energy is stored in the chemical system.

Rates vary

Temperature, concentration, surface area and catalysts can change how quickly reactions proceed.

Balanced equations track atoms

Stoichiometric coefficients show the proportions required by conservation of matter.

This page explains scientific concepts for general learning. It does not replace laboratory safety procedures, professional engineering guidance, or individualized medical advice.