Question

On the basis of quantum no.s,justify that the sixth period of the periodic table should have 32 elements.​

Answer 1

Answer:

Explanation:

In the Modern periodic table, each period starts with new principal quantum number .

And principal quantum number of element = period of that element.

hence, sixth period of the periodic table means principal quantum number = 6 e.g., n = 6

we know, A/C to Aufbau principle ,

in the ground state of any atoms , the orbitals are filled in order of their increasing energies .

so, for 6th period , electrons enter in 6s , 4f, 5d and 6p subshells.

hence, total number of orbitals = 1 { for 6s } + 7 { for 4f } + 5 { for 5d } + 3 { for 6p } = 16

Now, According to Paul's exclusion principle ,

Each orbital can accommodate maximum two electrons.

Hence, in 16 orbitals number of electrons = 2 × 16 = 32 .

Hence, in sixth period , there are 32 elements