Ac Al P N O S Cl F Ne Ar Rn I Si Xe He B C As 1 2 3 4 5 6 7 Elements in Group 0 of the periodic table are called the noble gases. They are unreactive because their atoms have stable arrangements of electrons. The atoms have eight electrons in their outermost shell, apart f...
Dmitri Mendeleev First Table made by arranging the 63 known elements in order of atomic weight grouping them by similarity of properties. Predicted the existence of new elements pointed out that some of the known atomic weights were wrong He left space on his table for new elements, and predict...