Write a short note on Dihydrogen.

(N/A) Occurrence of dihydrogen:
$(i)$ Dihydrogen is the most abundant element in the universe and is the principal element in the solar atmosphere.
(ii) However,due to its light nature,it is much less abundant ($0.15 \%$ by mass) in the earth's atmosphere.
(iii) In the combined form,it constitutes $15.4 \%$ of the earth's crust and the oceans.