Question

valency of element in period from left to right​

Answer 1

On moving from left to right in a period, the number of valence electrons decreases from 8 to 1. - As a result, valency across a period first increases and then decreases. - Valency increases from +1, +2, +3 till +4 in a period and then decreases -4, -3, -2, -1, 0.

Answer 2

Answer:

Valency in the periodic table across a period first increases and then decreases. There is no change going down a group.

Valency in the periodic table across a period first increases and then decreases. There is no change going down a group.However, this periodic trend is sparsely followed for heavier elements (elements with atomic number greater than 20), especially for lanthanide and actinide series.

Valency in the periodic table across a period first increases and then decreases. There is no change going down a group.However, this periodic trend is sparsely followed for heavier elements (elements with atomic number greater than 20), especially for lanthanide and actinide series.The greater the number of core electrons, the greater the shielding of electrons from the core charge of the nucleus. For this reason ionization energy is lower for elements lower down in a group, and polarizability of species is higher for elements lower down in a group. The valency does not change going down a group since the bonding behavior is not affected by the core electrons. However, non-bonding interactions such as those just cited are affected by core electrons...