An element Y is in second period and group 16 of the periodic table:
(i) Is it a metal or non-metal?
(ii) What is the number of valence electrons in its atom?
(iii) What is its valency?
(iv) What is the name of the element?
(v) What will be the formula of the compound formed by Y with sodium?
(i) This metal is surely non metal because metals are represented in the left side of periodic table.
(ii) Its electronic configuration is (2,6), so it has 6 valence electrons.
(iii) It has 6 electrons in its valence shell therefore the valency is 2.
(iv) The element which has configuration (2,6) is Oxygen.
(v) The formula with sodium id Na2Y.