Question

If the aufbau principle had not been followed, Ca (Z = 20) would have been placed in which block of periodic table? ​

Answer 1

Calcium (Ca),Z=20 {Z=atomic mass)

If afbau principle has not been followed then according to mosely periodic theory or modern periodic table (i.e.,the physical and chemical properties of element is periodic function of their atomic numbers)

So, calcium is of 2nd group, 3rd period and of d-block.

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