Concerning compounds cyanogen, Hydrogen cyanide and sodium cyanide.

Cyanogen = C2N2 (CN)2

Hydrogen Cyanide = HCN boils at 26C and yeilds an acid solution when added with water.

Sodium Cyanide = empirical formula NaCN is a solid melts at 564C

a) Assuming that the valencies of Hydrogen, Nitrogen and Carbon in these compounds are 1,3 and 4 respectively, draw structual formulae for hydrogen cyanide and cyanogen that are consistent with these valencies

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