The number of elements in the 4th period of periodic table is

The number of elements in the fifth period of periodic table is

If each orbital can hold a maximum of 3-electrons. The number of elements in 4^(th) period of periodic table is :

The number of elements in 5th and 6th period of periodic table are respectively

It each orbital can hold a maximum of three electrons, the number of elements in 9th period of periodic table (long form) are:

It each orbital can hold a maximum of three electrons, the number of elements in 9th period of periodic table (long form) are:

Number of elements in 6th period of modern periodic table is __________

The total number of elements in period 3 of the periodic table is: