Question

Which of the following series of elements have nearly the same atomic radii?

• A. $ \text{ }\!\!~\!\!\text{ F, Cl, Br, I} $
• B. $ \text{ }\!\!~\!\!\text{ Na, K, Rb, Cs} $
• C. $ \text{Li,}\,\text{Be,}\,\text{B,}\,\text{C} $
• D. $ \text{ }\!\!~\!\!\text{ Fe, Co, Ni, Cu} $

Answer 1

Answer: (D)

These are transition metals with the $ (n-1){{d}^{1-10}}n{{s}^{1-2}} $ configuration. The atomic and ionic radii of transition elements in a given series show a decreasing trend for first five elements and then becomes almost constant for next five elements.