Which of the following oxides of chromium is amphoteric in nature ?

2 3 2 5 3 basic Amphoteric acidic Cr O Cr O CrO / CrO Other d block amphoteric oxides ZnO 57. Which of the following statements is incorrect ? (a)The compounds formed by the 3d transition metals in lower valence states are ionic but those in higher valence states are covalent. (b)The 4d and 5d transition metals form less ionic compounds than do the 3d transition metals. (c) The compounds formed by the 3d transition metals are less ionic than the corresponding compounds formed by the 4d and 5d transition metals. (d) The ionization energies of 3d, 4d and 5d transition metals are greater