Question

How does the valency vary in a period on going from left to right in a periodic table
Pls answer this is 3 marks answer

Answer 1

When we move from left to right in periodic table valency increases. But after 4, it decreses also. The electrons present in the last shell determine the valency of a particular element.

Answer 2

we know modern periodic table is made on the basis of increasing atomic number. modern periodic law states that the physical and chemical function is the periodic function of their atomic number. the table contains 18 groups and 7 periods. In the period no of she'll of all elements remains same but their no of atom increases moving from left to right. as no of atom in outermost she'll determines the valancey of an element , valances vary from one to other. therefore valency vary in period on moving from left to right