The periodic table The periodic table is a chart of all the elements arranged in increasing atomic number. Group 1 alkali metals The Group 1 elements, also known as the alkali metals, all react ...

Chemists use symbols and formulae to represent elements and compounds ... The method chosen depends on the type of mixture. Atomic structure - AQA Atoms consist of a nucleus containing protons ...

and led to a new form of chemistry in which isotopes have taken the place of elements, and fractional atomic weights have been superseded by integral atomic numbers. Atomic Structure and Spectral ...