The Periodic Table

The Periodic Table

1. Mendeleev had to break his rule of having the elements in order of atomic mass because Iodine is meant to be before Tellurium but he found that Iodine had similar propeties to Fluorine, Chlorine and Bromine so he put them in the same row therefore he broke his own law.

2. Going down the line of the Alkali metals on the periodic table it goes in order of reactivity and softness going from Lithium - Francium. They also increase in density and decrease in melting and boiling points.

3. With the rules of the modern day periodic table it can be split into metals and non-metals with the metals dominating most of the left hand side and the non-metals on the right.