The metal ion with total number of electrons same as $S^{2-}$ is

Which one of the following is not isoelectronic with ${O^{2-}}$?

The atomic weight of an element is $39$. The number of neutrons in its nucleus is one more than the number of protons. The number of protons,neutrons,and electrons respectively in its atom would be

What is the number of electrons in a neutral atom that has $20$ protons in its nucleus?

An atom has the electronic configuration of $1s^2, 2s^2 2p^6, 3s^2 3p^6 3d^{10}, 4s^2 4p^5$. Its atomic weight is $80$. Its atomic number and the number of neutrons in its nucleus shall be

Which of the following is not a hydrogen-like species?