AgNO₃(aq.) was added to an aqueous KCl solution gradually and the conductivity of the solution was measured. The plot of conductance ($$\Lambda $$) versus the volume of AgNO₃ is

The major product of the following reaction is

Extra very pure N₂ can be obtained by heating

Among the given options, the compound(s) in which all the atoms are in one plane in all the possible conformations (if any) is(are)