Question

which of the following has maximum atomic radius? A. Lu B. Yb C. Ce D. Eu

Answer 1

The maximum atomic radius is of:

(D) Europium (Eu)

- The concept involved here is of Lanthanide Contraction.

- As we move from left to right in the lanthanides, the atomic size decreases due to it.

- But Europium shows a different trend.

- Despite coming in the middle of the lanthanides, its atomic radius is about 199 pm which is maximum among the given options.

- The atomic radius of the element Cerium (Ce) which lies on the left is about 183 pm.

- The atomic radius of the second last lanthanide Ytterbium (Yb) is 173 pm.

-The atomic radius of last lanthanide, i.e., Lutetium (Lu) is calculated as about 173 pm.