Q6 of 56 Page 1

In the modern periodic table, the elements 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?

The elements which have same number of valence electrons shows resemblance in their chemical properties.

So, we first need to find out the no. of valence electrons of every element.



The elements with atomic number 12 and 38 have the same valence number as that of Ca. So, their properties will be same.


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