Comprehension given below is followed by some multiple choice questions. Each question has one correct option. Choose the correct option.
In the modern periodic table, elements are arranged in order of increasing atomic numbers which is related to the electronic configuration. Depending upon the type of orbitals receiving the last electron, the elements in the periodic table have been divided into four blocks, viz s, p, d and f.
The modern periodic table consists of 7 periods and 18 groups. Each, period begins with the filling of a new energy shell. In accordance with the Aufbau principle, the seven periods (1 to 7) have 2, 8, 8, 18, 18, 32 and 32 elements respectively.
The seventh period is still incomplete. To avoid the periodic table being too long, the two series of f-block elements, called lanthonoids and actinoids are placed at the bottom of the main body of the periodic table
(ii) The last element of the p-block in 6th period is represented by the outermost electronic configuration.

Options

A. `7s^2 7p^6`
B. `5f^14 6d^10 7s^2 7p^0`
C. `4f^14 5d^10 6s^2 6p^6`
D. `4f^14 5d^10 6s^2 6p^4`

Answer

C

Explanation

Each period starts with the filling of electrons in a new principal energy shell. Therefore, 6th period starts with the filling of 6s-orbital and ends when 6p-orbitals are completely filled.
In between 4f and 5d-orbitals are filled in accordance with aufbau principle. Thus, the outmost electronic configuration of the last element of the p-block in the 6th period is `6s^2 4f^14 5d^10 6p^4 or 4f^14 5d^10 6s^2 6p^6`.