The total number of electrons present in anti-penultimate shell of calcium is

Q. The ratio of atomic numbers of two elements A and B is 1 : 2. The number of electrons present in the valence shell (3rd) of A is equal to the difference in the number of electrons present in the other two shells. Steps involved in the calculation of ratio of number of electrons present in a penultimate shell to antepenultimate shell of B are given below. Arrange them in the correct sequence.
(a) Calculation of atomic number of B.
(b) Calculation of valence electrons present in A.
(c) Calculation of atomic number of A.
(d) Calculation of number of electrons present in the penultimate shell and antepenultimate shell of B.
(e) Writing electronic configuration of B.

Q. The ratio of a number of valence shell electrons to the number of penultimate shell electrons in $Y^{-2}$ are:
(Atomic number of $Y$ is $34$)

Q. The ion that has different number of electrons in the ultimate and penultimate shells is :

Q. The outermost shell of a representative element contains $x$ electrons and penultimate shell contains $y$ electrons. The number of valence electrons could be:

Q. The number of electrons present in the 3rd shell of calcium is :