BRAINCAKEParticles
Revision notes for Particles in OCR Chemistry A (J248). Every lesson in BrainCake comes with R.E.C.I.P.E. recall steps, a quick check and spaced reviews.
- The particle model and states of matterThe particle model pictures every substance as a collection of tiny particles.
- Physical changes and chemical changesIn a physical change the particles keep their identity.
- Limitations of the particle modelIn the simple particle model, particles are drawn as small, solid, inelastic spheres, a bit like tiny bowling balls.
- Changing models of the atomScientists use models to explain what atoms are like, and a model is changed when new evidence does not fit it.
- The nuclear atomAn atom has a tiny nucleus at its centre.
- Size and scale of atomsAtoms are extremely small.
- Protons, neutrons and electronsAtoms are made of three types of sub-atomic particle.
- Atomic number, mass number and isotopesThe atomic number is the number of protons in an atom and it decides which element the atom is.