The number of s-electrons present in an ion with 55 protons in its unipositive state is

Step-by-step solution

The atom with 55 protons is caesium(Cs). The electronic configuration of Cs is 1 s 2 2 s 2 2 p 6 3 s 2 3 p 6 4 s 2 3 d 10 4 p 6 5 s 2 4 d 10 5 p 6 6 s 1 . The mono positive ion means one electron is removed from outermost orbital. Hence, the sum of electrons in 1 s ,   2 s ,   3 s ,   4 s ,   5 s orbitals are 10 .