Question

What are inner transition elements?

Decide which of the given atomic numbers are the numbers of inner transition elements: 29, 59, 74, 95, 102, 104.

Answer 1

The ‘f’ block elements i.e., in which the last electron enters the ‘f’ sub shell are called inner transition elements. These include lanthanides (58 – 71) and actinides (90 – 103). Thus, the elements with atomic numbers 59,95 and 102 are inner transition elements.