When glucose is reduced with sodium amalgam in aqueous solution, it gives

Mutarotation is the change of specific rotation of aqueous solution of:

$\left(\mathrm{a}\right)$ $\mathrm{\beta }$- glucose from $+19.2°$ to $+52.5°$.

$\left(\mathrm{b}\right)$ $\mathrm{\alpha }$- glucose from $+111°$ to $+52.5^{°}$.

$\left(\mathrm{c}\right)$ a sucrose from dextrorotatory to laevorotatory.

${\mathrm{CH}}_2\mathrm{OH}(\mathrm{CHOH}{)}_4\mathrm{CHO}+\mathrm{HCN}\to \mathrm{X}$

Identify the compound $\mathrm{X}$ in the above reaction?