Question

For the following reaction scheme, percentage yields are given along the arrow:

$X\, g$ and $y \,g$ are mass of $R$ and $U$, respectively.
(Use : Molar mass (in $g \,mol^{-1})$ of $H, C$ and $O$ as $1, 12$ and $16$, respectively)
The value of $y$ is _______.

Answer 1

Molar mass of ' $U$ ' $=122 \,g$ or $100 \,g$
$\underset{(0.1 \text { mole })}{ P } \xrightarrow{100 \%} \underset{(0.1 \text { mole })}{ S }$
$\underset{(0.1\text{mole})}{2S} \xrightarrow[(80\%)]{\text{Aldol condensation}} \underset{(\frac{0.1}{2} \times 0.8)}{T} \xrightarrow{80\%} \underset{(\frac{0.1}{2} \times 0.8\times .8)}{U}$
So, mass of '$U$' $=\frac{0.1}{2} \times 0.8 \times 0.8 \times 100=3.20\, gm$
Or
Mass of ' $U$ ' $=\frac{0.1}{2} \times 0.8 \times 0.8 \times 122=3.90\, gm$