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: Identify the electronic configuration of the given element.
The given electronic configuration is \[ [Kr]\,4d^{10}\,5s^{0} \] This configuration contains a completely filled \(4d\)-subshell and no electron in the \(5s\)-orbital.

Step 2: Recall the exceptional electronic configuration of Palladium.
Palladium (\(Pd\)) has atomic number \[ Z=46 \] Its experimentally observed electronic configuration is \[ [Kr]\,4d^{10}\,5s^{0} \] instead of the expected \[ [Kr]\,4d^{8}\,5s^{2} \] This occurs because a completely filled \(4d^{10}\) subshell is exceptionally stable.

Step 3: Check the other options.
For Silver (\(Ag\), \(Z=47\)), \[ [Kr]\,4d^{10}\,5s^{1} \] For Rhodium (\(Rh\), \(Z=45\)), \[ [Kr]\,4d^{8}\,5s^{1} \] For Technetium (\(Tc\), \(Z=43\)), \[ [Kr]\,4d^{5}\,5s^{2} \] None of these match the given configuration.

Step 4: Final conclusion.
Therefore, the element having electronic configuration \[ [Kr]\,4d^{10}\,5s^{0} \] is \[ \boxed{Pd} \] Hence, the correct option is \[ \boxed{(2)} \]