Question

Which of the following is position and chain isomer of ${\text{CH}}_3{\text{CH}}_2{\text{COCH}}_2{\text{CH}}_3$?

• A. ${\text{CH}}_3-\stackrel{\text{O}}{\stackrel{\text{||}}{\text{C}}}-\underset{{\text{CH}}_3}{\underset{\text{|}}{\text{CH}}}-{\text{CH}}_3$
• B. ${\text{CH}}_3-{\text{CH}}_2-{\text{CH}}_2{\text{CH}}_2-{\text{CH}}_2-\text{CHO}$
• C. ${\text{CH}}_3-{\text{CH}}_2-{\text{CH}}_2-{\text{CH}}_2-\text{OH}$
• D. ${\text{CH}}_3-{\text{CH}}_2-{\text{CH}}_2-{\text{CH}}_2-{\text{CH}}_3$

Answer 1

The correct option is A ${\text{CH}}_3-\stackrel{\text{O}}{\stackrel{\text{||}}{\text{C}}}-\underset{{\text{CH}}_3}{\underset{\text{|}}{\text{CH}}}-{\text{CH}}_3$

Compounds having same molecular formula and functional groups but functional groups are present at different position are called position isomers.

Compounds having the same molecular formula but difference in chain structure are called chain isomers.

All the compounds given in the options does not have same molecular formula ${\text{C}}_5{\text{H}}_{10}\text{O}$ as that of the given compound.

The compound ${\text{CH}}_3-\stackrel{\text{O}}{\stackrel{\text{||}}{\text{C}}}-\underset{{\text{CH}}_3}{\underset{\text{|}}{\text{CH}}}-{\text{CH}}_3$ has the same molecular formula to that of the given compound. They both consists of the same functional group but have difference in their position. Also, these compounds differ in their chain structure. Hence, it is the position and chain isomer of the given compound as it following the conditions for both.