Which of the following is the right electronic confiuration of the element palladium `(Z = 46)`?

Options

A. `[Kr] 4d^(10)`
B. `[Kr] 4d^(9)5s^(1)`
C. `[kr] 4d^(8)5s^(2)`
D. `[Kr]4d^(7)5s^(3)`

Answer

A

Explanation

Palladium has `46` electrons. We need `36` electrons `(2+8 +8 +18)` to complete the fourth period, leaving us with `10` more electrons to distribute among the `5s` (maximum `2e^(-)` and `4d` (maximum `10e^(-)s`) subshell. The three choice are `(1),(2)` and `(3)`. Since atomic palladium is diamagnetic, its electron configuration must be
`1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)4s^(2)4p^(6)4d^(10)`
or simply `[Kr] 4d^(10)`
Note that a diamagnetic substance is a substance that is not attracted by a magnetic field or is very slightly repelled by such a fiels. This property generally means that the sunstance has only paired electrons.