MCQ
The lanthanide contraction relates to
- AAtomic radii
- ✓Atomic as well as ${M^{3 + }}$ radii
- CValence electrons
- DOxidation states
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| List $I$ (Coordination entity) | List $II$ (Wavelength of light absorbed in $nm$) |
| $A$ ${\left[ CoCl \left( NH _3\right)_5\right]^{2+}}$ | $I$ $310$ |
| $B$ ${\left[ Co \left( NH _3\right)_6\right]^{3+}}$ | $II$ $475$ |
| $C$ ${\left[ Co ( CN )_6\right]^{3-}}$ | $III$ $535$ |
| $D$ ${\left[ Cu \left( H _2 O \right)_4\right]^{2+}}$ | $IV$ $600$ |
Choose the correct answer from the options given below
Statement $-I :$ The pentavalent oxide of group$- 15$ element. $E _{2} O _{5}$. is less acidic than trivalent oxide. $E _{2} O _{3}$. of the same element.
Statement $-II :$ The acidic character of trivalent oxide of group $15$ elements. $E _{2} O _{3}$. decreases down the group.
In light of the above statements. choose most appropriate answer from the options given below