Which of the statements is not true?

On passing $\mathrm{H}_{2}$ S through acidified $\mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}$ solution, a milky colour is observed.
$\mathrm{Na}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}$ is preferred over $\mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}$ in volumetric analysis.
$\mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}$ solution in acidic medium is orange.
$\mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}$ solution becomes yellow on increasing the $\mathrm{pH}$ beyond 7 .

Solution

$\mathrm{Na}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}$ is hygroscopic. ,

Asked in: JEE-TOPICTESTS-CHEMISTRY