Which of the following is amphoteric oxide ?

1. V2O5,Cr2O3 2. Mn2O7,CrO3
3. CrO,V2O5 4. V2O5,V2O4
NEETprep Answer: 
V2O5andCr2O3 are amphoteric oxide because both react with alkalies as well as acids.
Note In lower oxides, the basic characteris predominant while in higher oxides, the acidic character is predominant.