Question

A $1.84mg$ sample of polyhydric alcoholic compound ${}^{\prime }{X}^{\prime }$ of molar mass $92.0g/mol$ gave $1.344mL$ of $H_2$ gas at $STP$. The number of alcoholic hydrogens present in compound ${}^{\prime }{X}^{\prime }$ is ______.

Answer 1

Volume of $H_2$ gas $=1.344mL$.

Mole of $H_2$ gas $=\frac{1.344}{22400}=6\times {10}^{-5}$.

No of $H$ atoms per molecule of $H_2=2$.

Moles of $H$-atoms produced = $12\times {10}^{-5}$

No. of moles of organic compound =$=\frac{1.84\times {10}^{-3}}{92}=2\times {10}^{-5}$.


No. of -OH (hydroxyl group in one molecule) $=\frac{12\times {10}^{-5}}{2\times {10}^{-5}}=6$.

Note: Answer given is different from NTA.