1. Tardigrade
  2. Question
  3. Chemistry
  4. The reaction of K 3[ Fe ( CN )6] with freshly prepared FeSO 4 solution produces a dark blue precipitate called Turnbull's blue. Reaction of K 4[ Fe ( CN )6] with the FeSO 4 solution in complete absence of air produces a white precipitate X, which turns blue in air. Mixing the FeSO 4 solution with NaNO 3, followed by a slow addition of concentrated H 2 SO 4 through the side of the test tube produces a brown ring. Precipitate X is

Question Error Report

Thank you for reporting, we will resolve it shortly

Back to Question

Q. The reaction of $K _{3}\left[ Fe ( CN )_{6}\right]$ with freshly prepared $FeSO _{4}$ solution produces a dark blue precipitate called Turnbull's blue. Reaction of $K _{4}\left[ Fe ( CN )_{6}\right]$ with the $FeSO _{4}$ solution in complete absence of air produces a white precipitate $X$, which turns blue in air. Mixing the $FeSO _{4}$ solution with $NaNO _{3}$, followed by a slow addition of concentrated $H _{2} SO _{4}$ through the side of the test tube produces a brown ring.
Precipitate $X$ is

JEE AdvancedJEE Advanced 2021

Solution:

$FeSO_4 + K_4[Fe(CN)_6] \rightarrow \underset{\text{White ppt.}}{K_2[Fe(CN)_6]}$