The size of the iso-electronic species Cl-, Ar and Ca2+ is affected by:
nuclear charge
Prinicpal quantum number of valence shell
azimuthal quantum number of valence shell
electron-electron interaction in the outer orbitals
A.
nuclear charge
Isoelectronic species contain same number of shells so their size is effected by the nuclear charge.
The equation used to represents the electron gain enthalpy is
X(g) + e- → X-(g)
X(s) + e- → X-(g)
X(g) → X+(g) + e-
X(s) → X+(g) + e-
The electronic configuration of 59Pr ( praseodimium) is
[54Xe] 4f25d16s2
[54Xe] 4f15d16s2
[54Xe] 4f36s2
[54Xe] 4f35d2
An element in +2 oxidation state has 24 electrons. The atomic number of the element and the number of unpaired electrons in it respectively are
24 and 4
26 and 4
24 and 2
26 and 5
The element having greatest difference between its first and second ionization energies, is
K
Ca
Ba
Sc
Among the following, the isoelectronic specie (s) is/are
(i) O2-, F-, Na+, Mg2+
(ii) Na+, Mg+, Al3+, F-
(iii) N3-, O2-, F-, Ne
(i) and (ii)
(i), (ii) and (iii)
(ii) and (iii)
(i) and (iii)
The increasing order of the first ionisation enthalpies of the elements B, P, S and F is
B < S < P < F
F < S < P < B
P < S < B < F
B < P < S < F
The electronic configuration of Eu (Atomic no.63), Gd (Atomic no. 64) and Tb (Atomic no. 65) are
[Xe]4f6 5d1 6s2, [Xe] 4f7 5d1 6s2 and [Xe] 4f9 6s2
[Xe] 4f6 5d1 6s2 , [Xe] 4f7 5d1 6s2 and [Xe] 4f8 5d1 6s2
[Xe] 4f7 6s2, [Xe] 4f7 5d1 6s2 and [Xe] 4f9 6s2
[Xe] 4f7 6s2, [Xe] 4f7 5d1 6s2 and [Xe] 4f9 6s2