The Periodic Table of chemical elements represents
the material – “ingredients lists” of the present-day Universe.
- elements are arranged according to their atomic number – the same number of protons in the nucleus.
- in horizontal row – it’s called “periods and contain elements” that the same number of electron shells around the nucleus.
- in eight vertical columns – it’s called “group” that contain elements have similar chemical properties;
Group 0 – on the far right; this contains the inert noble gases.
Group IÂ – contains the alkali metals; surprisingly – hydrogen is chemically an alkali metal.
Group IIÂ – contains the alkali earth metals.
Group II to Group VIII – contains poor metals and non-metals; with the halogens in group 7.
Group II to Group III – metallic transition elements (which have incomplete inner electron shells) – located in the middle between group 2 and group 3.
Group II to Group III