Since then, the periodic table has evolved to reflect over 150 years of scientific development and understanding in chemistry and physics. Today, with 118 known elements, it is widely regarded as one ...

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 ...

Try these interactive flashcards based on GCSE chemistry past papers ... Mendeleev's periodic table, groups in the periodic table and transition metals. Atomic structure and the periodic table ...