Question

How does 6th period have 16 orbitals

Answer 1

in the sixth period electrons can be filled in 6s ,6p, 4f and 5d shells

here 6s have one orbital , 4f have 7 orbitals, 5d have 5 orbitals and 6p have three orbitals thus the sixth period is having 16 orbitals

Answer 2

In 6th period, electrons are filled in 6th energy shell.

The electrons are filled in the subshells following the sequence: 6s - 4f - 5d - 6p

Number of orbitals in the sub shells are:
6s : 1
4f : 7
5d : 5
6p : 3

Total orbitals = 1+7+5+3 = 16 orbitals