Question

Compound with molecular formula $C_3{H}_{6}O$ can show:

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• A. Positional isomerism
• B. Functional group isomerism
• C. Both positional isomerism and metamerism
• D. Metamerism

Answer 1

The correct option is B Functional group isomerism

For a compound with molecular formula $C_c{H}_h{X}_x{N}_n{O}_o$
$\text{Degree of unsaturation}=(c+1)-\frac{h}{2}-\frac{x}{2}+\frac{n}{2}$
Where, X = Halogen
c=number of carbon atom
h=number of hydrogen atom
n=number of nitrogen atom
o=number of oxygen atom
In $C_3{H}_{6}O$
$\text{Degree of unsaturation}=(3+1)-\frac{6}{2}=1$
$\text{Degree of unsaturation}=1$

No possible metamerism and positional isomers are possible.

Possible function group isomers are
$C{H}_3–C{H}_2–CH=O\text{\&}C{H}_3–CO–C{H}_3$. Therefore, functional group isomerism is the most appropriate.