Why the oxidation number of chromium in CrO 5 cannot be + 10??
Dear student,
If we want to find out Oxidation no. of Cr in CrO5 by general method it would be +10 which is wrong as in its real structure one Cr atom is attached to to 4 oxygen atoms & double-bonded with two O-atoms & single bonded with the rest two O-atoms. Oxygen being more electronegative attracts the shared electron towards itself. The double-bonded O-atoms retains 4 electrons while the single-bonded retains 2 electron, in that case one Cr-atom loses 6 electrons & it retains a positive charge of +6 so, its O.N. becomes +6.
Regards
If we want to find out Oxidation no. of Cr in CrO5 by general method it would be +10 which is wrong as in its real structure one Cr atom is attached to to 4 oxygen atoms & double-bonded with two O-atoms & single bonded with the rest two O-atoms. Oxygen being more electronegative attracts the shared electron towards itself. The double-bonded O-atoms retains 4 electrons while the single-bonded retains 2 electron, in that case one Cr-atom loses 6 electrons & it retains a positive charge of +6 so, its O.N. becomes +6.
Regards