Question

The element with the electronic configuration \([Kr]\,4d^{10}\,5s^{0}\) is:

• A. Ag
• B. Pd
• C. Rh
• D. Tc

Hint:

Palladium is a famous exception in electronic configurations. Its actual configuration is \[ [Kr]\,4d^{10}\,5s^{0} \] because a completely filled \(d^{10}\) subshell provides extra stability.

Answer 1

The Correct Option is B

Step 1: Recognise the exceptional configurations among Period 5 d-block elements.
Most d-block elements follow Aufbau, but Pd (Z=46) is unique: it achieves a completely filled 4d shell by emptying the 5s orbital entirely, giving [Kr] 4d\(^{10}\) 5s\(^0\).

Step 2: Eliminate other options.
Ag (Z=47) = [Kr] 4d\(^{10}\) 5s\(^1\); Rh and Tc do not have the full 4d\(^{10}\) 5s\(^0\) configuration. \[ oxed{Pd} \]