question_answer

A compound is formed by the substitution of two chlorine atoms by two hydrogen atoms in propane. What is the number of structural isomers possible?

Answer:

                Four structural isomers are possible. These are:                                    \[\underset{\text{1,}\,\text{1-Dichloropropane}}{\mathop{\overset{3}{\mathop{C}}\,{{H}_{3}}-\overset{2}{\mathop{C}}\,{{H}_{2}}-\underset{\begin{smallmatrix}  | \\  Cl \end{smallmatrix}}{\mathop{\overset{1}{\mathop{C}}\,H}}\,-Cl}}\,\]     \[\underset{\text{1,}\,2\text{-Dichloropropane}}{\mathop{\overset{3}{\mathop{C}}\,{{H}_{3}}-\underset{\begin{smallmatrix}  | \\  Cl \end{smallmatrix}}{\mathop{\overset{2}{\mathop{C}}\,H}}\,-\underset{\begin{smallmatrix}  | \\  Cl \end{smallmatrix}}{\mathop{\overset{1}{\mathop{C}}\,{{H}_{2}}}}\,}}\,\] \[\underset{\text{2,}\,\text{2-Dichloropropane}}{\mathop{\overset{3}{\mathop{C}}\,{{H}_{3}}-\underset{\begin{smallmatrix}  | \\  Cl \end{smallmatrix}}{\overset{\begin{smallmatrix}  Cl \\  | \end{smallmatrix}}{\mathop{{{C}^{2}}}}}\,-\overset{1}{\mathop{C}}\,{{H}_{3}}}}\,\]                      \[\underset{\text{1,}\,\,\text{3-Dichloropropane}}{\mathop{Cl-\overset{3}{\mathop{C}}\,{{H}_{2}}-\overset{2}{\mathop{C}}\,{{H}_{2}}-\overset{1}{\mathop{C}}\,{{H}_{2}}-Cl}}\,\]