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Which of the following statements are INCORRECT?
A. All the transition metals except scandium form MO oxides which are ionic.
B. The highest oxidation number corresponding to the group number in transition metal oxides is attained in $Sc_2O_3$ to $Mn_2O_7$.
C. Basic character increases from $V_2O_3$ to $V_2O_4$ to $V_2O_5$.
D. $V_2O_4$ dissolves in acids to give $VO_4^{3-}$ salts.
E. CrO is basic but $Cr_2O_3$ is amphoteric.
Choose the correct answer from the options given below:
A
B and C only
B
A and E only
C
B and D only
D
C and D only
Explanation
Basic character decreases from $V_2O_3$ to $V_2O_5$, and $V_2O_4$ gives $VO^{2+}$ salts, so C and D are incorrect.
Detailed Solution
The highest oxidation number corresponding to the group number in transition metal oxides is attained in $Sc_2O_3$ to $Mn_2O_7$.
CrO is basic but $Cr_2O_3$ is amphoteric.
Note: All the transition metals except scandium form MO oxides which are ionic (only for 3d series, this statement is true). Hence (A), (C) and (D) are incorrect. But not given in the options.