Chemistry · Rates of reaction

Reaction Rates.

Some reactions are over in a flash; others take years. Particles have to collide, and collide hard enough, before they can react. Change how often and how hard they collide, and you change how fast the reaction goes.

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Key words

Rate of reactionHow fast reactants are used up, or products are made, e.g. how much gas is given off each second

Collision theoryParticles must collide to react, and the collision must have enough energy. More successful collisions each second means a faster reaction

Activation energyThe smallest amount of energy a collision needs for the particles to react. Gentler collisions just bounce apart

ConcentrationHow many particles are packed into a given volume. Higher concentration, more frequent collisions

Surface areaHow much of a solid is exposed. Only surface particles can be hit, so a powder reacts faster than a lump

CatalystA substance that speeds up a reaction by giving it a route that needs less energy. It is not used up

See it for real: the Bunsen Burner Lab (heat and oxygen), the Metal Reactions Lab (acids fizzing with metals), and Structure & Properties (how particles move as they're heated).

Narration voice: Max, generated with ElevenLabs.