Question

why valency of nitrogen is 3

Answer 1

Atomic number of nitrogen is 7.. Which means electronic configuration is 2,5....thus in the last orbit there are 5 electrons...thus they need 3 more electrons..so that nitrogen is stable...as there should be 8 electrons in the last she'll..to make the element stable..

Answer 2

NITROGEN HAS 5 ELECTRONS. TWO ELECTRONS IN 1st SHELL AND 3 ELECTRONS IN OUTERMOST SHELL.SO TO GET CONFIGURATION IT HAS TO FORM TRIPLE BOND.SO IT NEEDS STILL 3 ELECTRONS TO GET STABLE.HENCE ITS VALENCY IS 3.