BCECE Engineering BCECE Engineering Solved Paper-2014

  • question_answer
    Which one of the following conversions involve change in both hybridisation and shape?

    A) \[C{{H}_{4}}\to {{C}_{2}}{{H}_{6}}\]        

    B) \[N{{H}_{3}}\to NH_{4}^{+}\]

    C)  \[B{{F}_{3}}\to BF_{4}^{-}\]      

    D) \[{{H}_{2}}O\to {{H}_{3}}{{O}^{+}}\]

    Correct Answer: C

    Solution :

    (a)\[\underset{\begin{smallmatrix}  \text{Hybridisation s}{{\text{p}}^{\text{3}}} \\  \text{Structure tetrahedral} \end{smallmatrix}}{\mathop{\underset{4bp+0/p}{\mathop{C{{H}_{4}}}}\,}}\,\to \underset{tetrahedral}{\mathop{\underset{s{{p}^{3}}}{\mathop{\underset{4bp}{\mathop{C{{H}_{3}}}}\,}}\,-\underset{s{{p}^{3}}}{\mathop{\underset{4bp}{\mathop{C{{H}_{3}}}}\,}}\,}}\,\] \[\underset{\begin{smallmatrix}  \text{Hybridisation s}{{\text{p}}^{\text{3}}} \\  \text{Structure pyramidal} \end{smallmatrix}}{\mathop{\underset{3bp+1/p}{\mathop{N{{H}_{3}}}}\,}}\,\xrightarrow[{}]{}\underset{{}}{\mathop{\underset{tetrahedral}{\mathop{\underset{s{{p}^{3}}}{\mathop{\underset{4bp}{\mathop{NH_{4}^{+}}}\,}}\,}}\,}}\,\] \[\underset{\begin{smallmatrix}  \text{Hybridisation s}{{\text{p}}^{\text{2}}} \\  \text{Structure trigonal planar} \end{smallmatrix}}{\mathop{\underset{3bp}{\mathop{B{{F}_{3}}}}\,}}\,\xrightarrow{{}}\underset{\text{tetrahedral}}{\mathop{\underset{s{{p}^{3}}}{\mathop{\underset{4bp}{\mathop{BF_{4}^{-}}}\,}}\,}}\,\] \[\underset{\begin{smallmatrix}  \text{Hybridisation s}{{\text{p}}^{3}} \\  \text{Structure angular} \end{smallmatrix}}{\mathop{\underset{2bp+2lp}{\mathop{{{H}_{2}}O}}\,}}\,\xrightarrow{{}}\underset{\text{pyramidal}}{\mathop{\underset{s{{p}^{3}}}{\mathop{\underset{3bp+1//p}{\mathop{{{H}_{3}}{{O}^{+}}}}\,}}\,}}\,\] Thus, conversation of \[\text{B}{{\text{F}}_{3}}\]into \[BF_{4}^{-}\]involves        change in both hybridisation and shape.          


You need to login to perform this action.
You will be redirected in 3 sec spinner