The major product H of the given reaction sequence is

$$C{H_3} - C{H_2} - CO - C{H_3}\buildrel {\overline C N} \over \longrightarrow G\mathrel{\mathop{\kern0pt\longrightarrow} \limits_{Heat}^{95\% \,{H_2}S{O_4}}} H$$

$$NiC{l_2}{\{ P{({C_2}{H_5})_2}({C_6}{H_5})\} _2}$$ exhibits temperature-dependent magnetic behaviour (paramagnetic/diamagnetic). The coordination geometries of Ni²⁺ in the paramagnetic and diamagnetic states are, respectively,