Biomolecules Question 12
Question 12 - 2024 (31 Jan Shift 2)
A compound ( $\mathrm{x}$ ) with molar mass $108 \mathrm{~g} \mathrm{~mol}^{-1}$ undergoes acetylation to give product with molar mass $192 \mathrm{~g} \mathrm{~mol}^{-1}$. The number of amino groups in the compound $(\mathrm{x})$ is ________
Show Answer
Answer (2)
Solution
Formula: Acetylation
$\mathrm{R}-\mathrm{NH}{2}+\mathrm{CH}{3}-\stackrel{\substack{\mathrm{O} \ ||}}{\mathrm{C}}-\mathrm{Cl} \longrightarrow \mathrm{R}-\mathrm{NH}-\stackrel{\substack{\mathrm{O} \ ||}}{\mathrm{C}}-\mathrm{CH}_{3}$
Gain in molecular weight after acylation with one $-\mathrm{NH}_{2}$ group is 42 .
Total increase in molecular weight $=84$
$\therefore$ Number of amino group in $x=\frac{84}{42}=2$
