• # question_answer Which of the following compounds is not chiral  [AIEEE 2004] A) 1-chloro-2-methyl pentane B) 2-chloropentane C) 1-chloropentane D) 3-chloro-2-methyl pentane

To be optically active the compound or structure should possess chiral or a symmetric centre but in the rest of the structures it is present. $\underset{1\text{ chloropentane}}{\mathop{H-\overset{Cl}{\mathop{\overset{|}{\mathop{\underset{H}{\mathop{\underset{|}{\mathop{C}}\,}}\,}}\,}}\,-\overset{H}{\mathop{\overset{|}{\mathop{\underset{H}{\mathop{\underset{|}{\mathop{C}}\,}}\,}}\,}}\,-\overset{H}{\mathop{\overset{|}{\mathop{\underset{H}{\mathop{\underset{|}{\mathop{C}}\,}}\,}}\,}}\,-\overset{H}{\mathop{\overset{|}{\mathop{\underset{H}{\mathop{\underset{|}{\mathop{C}}\,}}\,}}\,}}\,-\overset{H}{\mathop{\overset{|}{\mathop{\underset{H}{\mathop{\underset{|}{\mathop{C}}\,}}\,}}\,}}\,-H}}\,$    $\underset{2\text{ chloropentane}}{\mathop{H-\overset{H}{\mathop{\overset{|}{\mathop{\underset{H}{\mathop{\underset{|}{\mathop{C}}\,}}\,}}\,}}\,-\overset{Cl}{\mathop{\overset{|}{\mathop{\underset{H}{\mathop{\underset{|}{\mathop{C}}\,}}\,}}\,}}\,-\overset{H}{\mathop{\overset{|}{\mathop{\underset{H}{\mathop{\underset{|}{\mathop{C}}\,}}\,}}\,}}\,-\overset{H}{\mathop{\overset{|}{\mathop{\underset{H}{\mathop{\underset{|}{\mathop{C}}\,}}\,}}\,}}\,-\overset{H}{\mathop{\overset{|}{\mathop{\underset{H}{\mathop{\underset{|}{\mathop{C}}\,}}\,}}\,}}\,-H}}\,$ $\underset{1\text{ chloro -2 methyl pentane}}{\mathop{H-\overset{Cl}{\mathop{\overset{|}{\mathop{\underset{H}{\mathop{\underset{|}{\mathop{C}}\,}}\,}}\,}}\,-\overset{C{{H}_{3}}}{\mathop{\overset{|\,\,\,\,\,\,\,\,\,}{\mathop{\underset{H\,\,\,}{\mathop{\underset{|\,\,\,\,\,\,\,}{\mathop{C-}}\,}}\,}}\,}}\,\overset{H}{\mathop{\overset{|}{\mathop{\underset{H}{\mathop{\underset{|}{\mathop{C}}\,}}\,}}\,}}\,-\overset{H}{\mathop{\overset{|}{\mathop{\underset{H}{\mathop{\underset{|}{\mathop{C}}\,}}\,}}\,}}\,-\overset{H}{\mathop{\overset{|}{\mathop{\underset{H}{\mathop{\underset{|}{\mathop{C}}\,}}\,}}\,}}\,-H}}\,$   $\underset{3\text{ chloro 2 methyl pentane}}{\mathop{H-\overset{H}{\mathop{\overset{|}{\mathop{\underset{H}{\mathop{\underset{|}{\mathop{C}}\,}}\,}}\,}}\,-\overset{C{{H}_{3}}}{\mathop{\overset{|\,\,\,\,\,\,\,\,\,}{\mathop{\underset{H\,\,\,}{\mathop{\underset{|\,\,\,\,\,\,\,}{\mathop{C-}}\,}}\,}}\,}}\,\overset{Cl}{\mathop{\overset{|}{\mathop{\underset{H}{\mathop{\underset{|}{\mathop{C}}\,}}\,}}\,}}\,-\overset{H}{\mathop{\overset{|}{\mathop{\underset{H}{\mathop{\underset{|}{\mathop{C}}\,}}\,}}\,}}\,-\overset{H}{\mathop{\overset{|}{\mathop{\underset{H}{\mathop{\underset{|}{\mathop{C}}\,}}\,}}\,}}\,-H}}\,$