Question

Which of the following orbital has most energy in multi-electron system?

• A. 3s
• B. 4p
• C. 4d
• D. 4s

Answer 1

The correct option is C

4d

Try to use Bohr - Bury rule of (n + l) here.

$\to$ Whichever is having more value of (n + l) value will have more energy.

$\Rightarrow$ 3s $\Rightarrow$ 3 + 0 = 3

$\Rightarrow$ 4p $\Rightarrow$ 4 + 1 = 5

$\Rightarrow$ 3d $\Rightarrow$ 3 + 2 = 5

$\Rightarrow$ 4s $\Rightarrow$ 4 + 0 = 4

Now, between 3d and 4p, because they have same (n + l) value, whichever orbitals 'n' is greater, will have more energy.

So, 4p will have most energy.