Which of the following pairs of elements have same number of electrons in their outermost shell ? — Periodic Table and Periodicity Chemistry Question

💡 Solution & Explanation

Step 1: Metallic character corresponds to the ease with which an atom loses its valence electrons (electropositivity). Step 2: Going down a group, atomic size increases and the outer electrons are less tightly bound by the nucleus, resulting in lower ionization energy and increased metallic character. Step 3: Moving from left to right across a period, atomic size decreases and effective nuclear charge increases, making it harder to remove valence electrons. Therefore, metallic character decreases across a period.