The sun heats up the air at different rates. Weather is caused by uneven heating
(1) Francium - 0.7 Lowest
(2) Barium - 0.89
(3) Aluminium- 1.61
(4) Copper - 1.90
(5) Phosphorus - 2.19
(6) Flurorine - 3.98 Highest electronegativity in periodic lable
<span>There is a direct correlation between the period number and the energy level for valence electrons. For example, the H and He elements, in period 1, have their outer electrons in the energy level "1". This continues down the rows: all the elements in period 2 have their principal energy level as n = 2, period 3 has n = 3, and so on.</span>
