How to find valency

How will you find the valency of chlorine, sulphur and magnesium ?

(a) Define the following terms: (i) Valency, (ii) Atomic size (b) How do the valency and the atomic size of the element vary while going from left to right along a period in the modern periodic table?

How does valency and valence electrons vary on moving from left to right in II period

How does valency change within a group of the periodic table?

An element X form a hydroxide X(OH)_(3) . Find the valency of X

An element belongs to 3^(rd) period and group 17 of the modern periodic table, find out: (a) The number of valence electrons and valency (b) Lewis structure of its compound with hydrogen (c) Electronic configuration of this element

The sum of number of valence electrons and valency of an element with atomic number 15 is_____.

The equivalent weight of an element is 4 . Its chloride has a vapour density 59.25 . Find the valency of element.

In a regular B_(12) icosahedran : How many valence electrons are there ?