. Write the number of periods the modem periodic table has


Write the number of periods the modem periodic table has. How do the valency and metallic character of elements vary on moving from left to right in a period? How do the valency and atomic size of elements vary down a group

Best Answer

There are seven periods in the modem  periodic table

 

On moving from left to right in a period, the valency of elements increases from 1to 4 and then decreases to 0

 

On moving from left to right in a period, the metallic characters of elements decreases as the electropositive character of elements decreases on moving from left to right in a period

 

All  the  elements  in  a  group  have  same  valency  because  the  number  of valence electrons in a group  is same

 

On going down in a group of the periodic table, the size of atoms increases because a new shell of electrons is added to the atoms at every  step  on  moving  down  in a group

Talk to Our counsellor