Inertness of Noble Gases: The combining capacity of atoms of elements to form molecules is known as valency. Different elements have different combining capacities. For instance, chlorine combines with one atom of hydrogen to form HCl; oxygen combines with two atoms of hydrogen to form H2O and nitrogen combines three atoms of hydrogen to form NH3 etc. With respect to hydrogen, the combining capacities of chlorine, oxygen and nitrogen are 1, 2 and 3, respectively. Thus, valency may be defined as the number of hydrogen atoms which can combine with one atom of the element. The element next to hydrogen … Continue reading Inertness of Noble Gases