Q6
In the modern periodic table, the element Calcium (atomic number = 20) is surrounded by elements with atomic numbers 12, 19, 21 and 38. Which of these elements has physical and chemical properties resembling those of Calcium and why?
Solution
Ca (atomic number = 20) (electronic configuration = 2, 8, 8, 2)
Element with
atomic number = 12 (electronic configuration = 2, 8, 2)
atomic number = 19 (electronic configuration = 2, 8, 8, 1) atomic number = 21 (electronic configuration = 2, 8, 8, 3) atomic number = 38 (electronic configuration = 2, 8, 18, 8, 2)
Elements with atomic number 12 and 38 have physical and chemical properties resembling with Ca because valence electrons in these elements are same as Ca, i.e., 2. As properties of an element depend on its valence electrons.
