Science
What is Chemical reactions?
A chemical reaction is a process where substances (reactants) rearrange their atoms to form new substances (products) with different properties. Burning, rusting, and digestion are all chemical reactions.
See it, don’t just read it.
Watch a 2-minute lesson with voice + animation that explains chemical reactions.
Key things to understand
- 1Bonds between atoms break and re-form, making new substances.
- 2Atoms are rearranged, never created or destroyed (conservation of mass).
- 3Signs include color change, gas, heat, light, or a new solid.
- 4Reactions can release energy (exothermic) or absorb it (endothermic).
Frequently asked questions
- What happens in a chemical reaction?
- Reactant molecules break and re-form bonds, rearranging atoms into new product molecules.
- What are signs of a chemical reaction?
- Color change, bubbles (gas), temperature change, light, or a new solid (precipitate) forming.
- What's the difference between a physical and chemical change?
- A physical change alters form (like melting); a chemical change creates new substances.