NEET2023Chemistryd and f Block ElementsActual
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 2 O 3 to Mn 2 O 7 . C. Basic character increases from V 2 O 3   to   V 2 O 4   to   V 2 O 5 . D. V 2 O 4 dissolves in acids to give VO 4 - 3 salts. E. CrO is basic
Options
- AB and C only
- BA and E only
- CB and D only
- DC and D only
Correct answer
D. C and D only
Step-by-step solution
Lower oxidation state oxides are ionic. The highest oxidation number in the oxides, coincides with the group number and is attained in Sc 2 O 3 to Mn 2 O 7 . The structure of V 2 O 5 is more covalent than that of V 2 O 3 and V 2 O 4 , which makes it more acidic. As a result, the basicity of V 2 O 5 is greater than that of V 2 O 4 , which is in turn greater than that of V 2 O 3 . Here in option C they have gien the increasing order of acidic character. So Option C is wrong. V 2 O 4 dissolves in acids to give VO 2 +