Question

When pyridine (Py) is added to the ether layer containing blue peroxide of chromium, the compound obtained is:

• A. $Py.Cr{O}_3$
• B. $Py.Cr{O}_5$
• C. $Py.Cr{O}_4$
• D. $Py.Cr{O}_2$

Answer 1

Answer: (B)

$Py.Cr{O}_5$

Diethyl ether is commonly used for the identification of chromium compounds and for the identification of peroxide. The blue reaction product is a diperoxo chromium oxide complex ($CrO(O_2{)}_2.Solvent$) which is subsequently extracted into ether. Therefore when solvent is pyridine ($Py$) compound is ($CrO(O_2{)}_2.Py$)