BRAINCAKEAtomic structure and the periodic table
Revision notes for Atomic structure and the periodic table in AQA Combined Science: Trilogy (8464). Every lesson in BrainCake comes with R.E.C.I.P.E. recall steps, a quick check and spaced reviews.
- Atoms, elements and compoundsAll substances are made of atoms.
- MixturesA mixture consists of two or more elements or compounds that are not chemically combined.
- The development of the model of the atom (common content with physics)A scientific model changes when new experimental evidence does not fit it.
- Relative electrical charges of subatomic particlesThe nuclear model describes an atom as a small nucleus at the centre, made of protons and neutrons, with electrons around it.
- Size and mass of atomsAtoms are very small.
- Relative atomic massMost elements are a mixture of isotopes, and the isotopes have different masses.
- Electronic structureThe electrons in an atom are arranged in shells, which are also called energy levels.
- The periodic tableThe periodic table lists the elements in order of atomic number, which is the number of protons in the nucleus of an atom.
- Development of the periodic tableBefore protons, neutrons and electrons were discovered, scientists could not use atomic number to sort the elements.
- Metals and non-metalsElements that react to form positive ions are metals.
- Group 0The elements in Group 0 are called the noble gases: helium, neon, argon, krypton, xenon and radon.
- Group 1The elements in Group 1 are known as the alkali metals.
- Group 7The elements in Group 7 are known as the halogens: fluorine, chlorine, bromine and iodine.