A) \[{{Y}^{3}}^{+}<L{{a}^{3+}}<E{{u}^{3+}}<L{{u}^{3+}}\]
B) \[{{Y}^{3}}^{+}<L{{u}^{3+}}<E{{u}^{3+}}<L{{a}^{3+}}\]
C) \[L{{u}^{3+}}<E{{u}^{3+}}<L{{a}^{3+}}<{{Y}^{3+}}\]
D) \[L{{a}^{3+}}<E{{u}^{3+}}<L{{u}^{3+}}<{{Y}^{3+}}\]
Correct Answer: B
Solution :
The correct order of ionic radii of \[{{Y}^{3+}},\,L{{a}^{3+}},\,E{{u}^{3+}},\]and \[L{{u}^{3+}}\]is\[{{Y}^{3+}}<L{{u}^{3+}}<E{{u}^{3+}}\]\[<L{{a}^{3+}}\] because Eu and Lu are the members of lanthanide series so they show lanthanide contraction and La is the representative element of all elements of such series and\[{{Y}^{3+}}\] ion has lower radii as compared to \[L{{a}^{3+}}\]because it lies immediately above it in the periodic table.You need to login to perform this action.
You will be redirected in
3 sec