An acidified solution of potassium chromate was layered with an equal volume of amyl alcohol. When it was shaken after the addition of 1 mL of 3 % H 2 O 2, a blue alcohol layer was obtained. The blue color is due to the formation of a chromium (VI) compound ' X '. What is the number of oxygen atoms bonded to chromium through only single bonds in a molecule of X ?

Question

An acidified solution of potassium chromate was layered with an equal volume of amyl alcohol. When it was shaken after the addition of 1 mL of 3 % H 2 O 2, a blue alcohol layer was obtained. The blue color is due to the formation of a chromium (VI) compound ' X '. What is the number of oxygen atoms bonded to chromium through only single bonds in a molecule of X ? (A)  (B)  (C)  (D)

Tardigrade Admin · Accepted Answer

CrO42- <=>[H+][OH] Cr2O72- Cr2O72- + H2O + H+ arrow underset textChromium peroxide(blue)CrO5

So, number of oxygen atoms attached to Cr through single bond = 4

CrO42−​HX+OH​Cr2​O72−​ Cr2​O72−​+H2​O+H+→Chromium peroxide(blue)CrO5​​ So, number of oxygen atoms attached to Cr through single bond =4

$C r O_{4}^{2 -} H X^{+} OH C r_{2} O_{7}^{2 -}$
$C r_{2} O_{7}^{2 -} + H_{2} O + H^{+} \to Chromium peroxide(blue) C r O_{5}$

So, number of oxygen atoms attached to $C r$ through single bond $= 4$