The tutorial gives an opportunity to practise skills and bring together ideas introduced in previous lessons. History Mendeleef placed the elements in order of atomic weight on the Periodic Table. Rutherford and Moseley refined the Periodic Table by using atomic number. The most metallic elements are at the bottom left of the Table. Non-metals are restricted to the top right of the Table.
Metals lose electrons in chemical reactions, non-metals gain electrons or form covalent bonds.
The transition elements are typical metals that lie between the main parts of the Periodic Table. Alkaline Earths Group 2 metals are similar to group 1 but are less reactive. Calcium and magnesium both burn in air. 2 Group 2 metals react with H 2 O to form hydroxides and hydrogen. Physical properties of group 2 low densities, but not as low as group 1 higher melting points than group 1.