question_answer 1)

  What   is   meant   by   hybridisation?   Compound \[C{{H}_{2}}=C=C{{H}_{2}}\] contains \[sp\]or \[s{{p}^{2}}\]hybridised carbon atoms. Will it be a planar molecule?

Answer:

    Allene   are   cumulative   dienes   \[{{H}_{2}}\overset{1}{\mathop{C}}\,=\overset{2}{\mathop{C}}\,=\overset{3}{\mathop{C}}\,{{H}_{2}}\] (Propa-1, 2-diene). In allene \[{{C}_{1}}\]and \[{{C}_{3}}\] are \[s{{p}^{2}}\]?hybridized and \[{{C}_{2}}\] is \[sp\]hybridized. The two \[\pi \]-bonds are present in the central carbon, one each from \[{{p}_{y}}\] and \[{{p}_{z}}\] orbitals thus, overlapping planes in \[{{C}_{1}}\] and \[{{C}_{3}}\] are also different.