Question

Why do metallic character decreases from left to right in a period?

Answer 1

as we move left to right in a period the size of elements decreases due to which the attraction from the nucleus for the outer most shell increases and the electrons are not easily lost but gained which is a non metallic characteristics so metallic charteristics

Answer 2

Along the period, from left to right, the effective nuclear charge increases due to increase in no. of protons due to which forces of attraction b/w nucleus and valence electrons increases and ability to lose electrons (i.e metallic character) decreases.