Question

Which are the true statements regarding ionization energy of d-series elements?
A. Ionization enrgy of Mn is greater than Cr
B. Ionization energy of `Pd gt Rh` and `Pd gt Ag`
C. Ionization energy decreases from `3d` to 4d transition series but it increases from `4d` to `5d` series
D. Ionization energy of `Mo` is greater than W

Answer 1

Correct Answer - A::B::C
(i) In both Mn and Cr the electron is to be removed from 4s but in Mn effective nuclear charge is more.
(ii) `._(46)Pd` has more effective nuclear charge than `._(45)Rh`. So `IE_(1)` of `Pd gt Rh`. In Pd the electronic configuration is `4d^(10)5s^(0)`, whereas in water in silver it is `4d^(10)5s^(-1)`. the remove an electron from stable `d^(10)` configuration in Pd energy required is more than in Ag
(iii) In a transition group generally atomic size increases from first element to second element. So IE decreases. Bu the atomic size of `2`nd and `3`rd elements are alost equal due to langthanide contraction. As the effective nuclear charge is more in 3rd element i.e., `5d` series IE values are more.
(iv) As explained above W will have more IE Than