Question

In the modern periodic table, the element calcium (atomic number = 20) is sorrounded 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?

Answer 1

magnesium( atomic number 12) and strontium (atomic number 38) have physical and chemical properties resembling calcium (atomic number 20) since they belong to same group( i.e group 2) and elements of same group have similar properties.

hope that helps.

Answer 2

Explanation:

The element with atomic number 12 has same chemical properties as that of calcium. This is because both of them have same number of valence electrons (2).