On heating,hydrazoic acid forms:

When conc. $H_2SO_4$ comes in contact with sugar,it becomes black due to

Number of nucleons in $D_2$ molecule is

Complete the following chemical reactions:
$(i) \ PbS_{(s)} + H_2O_{2_{(aq)}} \to $
$(ii) \ MnO_{4_{(aq)}}^{-} + H_2O_{2_{(aq)}} \to $
$(iii) \ CaO_{(s)} + H_2O_{(g)} \to $
$(iv) \ AlCl_{3_{(g)}} + H_2O_{(l)} \to $
$(v) \ Ca_3N_{2_{(s)}} + H_2O_{(l)} \to $
Classify the above into $(a)$ hydrolysis,$(b)$ redox and $(c)$ hydration reactions.

Deuterium differs from hydrogen in

Dihydrogen of high purity $(>99.95 \%)$ is obtained through: