# The period number in the long form of the periodic table is equal to

–1 vote
1 view
The period number in the long form of the periodic table is equal to
(a) magnetic quantum number of any element of the period.
(b) atomic number of any element of the period.
(c) maximum principal quantum number of any element of the period.
(d) maximum Azimuthal quantum number of any element of the period.

answered Mar 6, 2018 by (-1,032 points)
(c) Since each period starts with the filling of electrons in a new principal quantum number, therefore, the period number in the long form of the periodic table refers to the maximum principal quantum number of any element in the period.
Period number = maximum n of any element
(where, n = principal quantum number).

–1 vote