Question

9. In the Modern Periodic Table, calcium (atomic number 20) is surrounded by
elements with atomic numbers 12, 19, 21 and 38. Which of these have physical
and chemical properties resembling calcium?
in Mendeléey's Periodic Table​

Answer 1

Answer:

The electronic configuration of Ca(20) is =2,8,8,2

Number of valance electrons =2

The elements with atomic number 12 and 38 both have 2 valence electrons in their outer shell but elements with 19 has 1 valance electron and 21 has 3 valance electrons. Therefore elements with atomic number 12 and 38 have physical and chemical properties resembling calcium...

Answer 2

Answer:

Calcium, with atomic number 20 has an electronic configuration of – 2,8,8,2. ... Hence, elements with atomic numbers 12 and 38 will have physical and chemical properties resembling calcium. Note: Elements of a period do not have similar electronic configuration.

Explanation:

Follow me please

............XD