Question

Which of the following oxides are basic ?
A. `Mn_2O_7 and V_2O_3`
B. `V_2O_3 and CrO`
C. `CrO and Cr_2O_3`
D. `V_2O_5 and V_2O_3`

Answer 1

Correct Answer - B
In case of transition metal oxides, the oxides with metals in lower oxidation states are basic in nature. ltbRgt O.S. of Mn in `Mn_2O_7=+7, V" in "V_2O_3= +3, V " in " V_2O_5 = +5`, Cr in CrO and `Cr_2O_3` transition metal ion is in lower oxidition state but `Cr_2O_3` is amphoteric in nature.
Hence `V_2O_3` and CrO are basic in nature.