What is the valency of the atomic number 50?

As Malcolm replied, 2+ or 4+. There is a tin sesquisulphide, Sn2S3, which suggests trivalent 3+ but the tin coordination and valency in this phase is mixed 2+ and 4+ giving nominal 3+. read more

A lithium atom has one outer shell electron, so it’s usual valence is +1, but it can lose the electron and have a valence of -1. This is a table of the valences or oxidation states of the elements. The most common valences are in BOLD. read more

The oxidation state of an atom in a molecule gives the number of valence electrons it has gained or lost. In contrast to the valency number, the oxidation state can be positive (for an electropositive atom) or negative (for an electronegative atom). Elements in a high oxidation state can have a valence higher than four. read more

The words valence and valency have two related meanings in chemistry. Valence describes how easily an atom or radical can combine with other chemical species. This is determined based on the number of electrons that would be added, lost or share if it reacts with other atoms. read more