Unlike Phosphorus, nitrogen shows little tendency for catenation. Why?

Why nitrogen is less reactive?

How would you account for the following : Sulphur has a great tendency for catenation than oxygen.

Out of white phosphorus and red Phosphorus, which one is More reactive and why?

Molecular nitrogen is not particularly and reactive. Why?

The isotope Phosphorus-33 undergoes beta - decay to form Sulphur-33, which is stable.The half - life of Phosphorus-33 is 24.8 days. Show that the decay constant of Phosphorus -33 is 3.23 xx 10^(-7) s^(-1) .

Sulphur exhibits greater tendency for catenation than seleniun. Explain why?