Answer
Selenide, Se-2; bromide, Br-1; and rubidium cation, Rb+1 are all isoelectronic to krypton; that is they all have 36 electrons.
Work Step by Step
Selenide, Se-2; bromide, Br-1; and rubidium cation, Rb+1 are all isoelectronic to krypton; that is they all have 36 electrons.