Test: Group-15 Elements - NEET

Nitrogen shows different oxidation states ranging from -3 to +5 in its compound

O.S. of N in N₃H = -1/3
O.S.of N in NH₃ = -3
O.S. of N in NH₂OH = -1
O.S. of N in NH₂H₄ = -2

N2O = +1, NO = +2, NO2 = +4,= +5,   = -3
increasing order of oxidation state will be
< N₂O < NO < NO₂ < 

pπ - pπ bonding in nitrogen is strong hence it can form triple bond with another N. Single N−N bond is weaker than P−P bond due to high interionic repulsion of non-bonding electrons. Hence, N=N is stable and P₂ is not.

H₂O and NH₃ have abnormally high boiling boilling points of their tendency to form hydrogen bonds. NH₃ has hiigher boiling point than phosphine and then boiling pont increase down the group because of increase in size . Hence the order of boiling point will be 
H₂​O > SbH₃​ > NH₃​ > AsH₃​ > PH₃