The valency of an element is linked to how many electrons an atom must gain or lose to achieve the same electronic structure as a noble gas i.e., have a full outer shell. For example an element in ...

IT has been shown by one of us 1 that, at ordinary temperatures, the structure of nickel oxide is slightly deformed from face-centred cubic symmetry. Later work 2 proved that at − 180° C.

The Earth has a layered structure made up of the core, the mantle and the crust. Different elements are present in different parts of the Earth’s structure. The crust is made from enormous ...