Consider the ground state of Cr atom $$(Z = 24)$$. The number of electrons with the azimuthal quantum numbers $$l = 1$$ and $$2$$ are respectively

Chromium has atomic number $$Z=24$$. Its ground state electronic configuration is

$$1s^22s^22p^63s^23p^64s^13d^5$$

Chromium shows an exceptional configuration because a half-filled $$3d^5$$ subshell is more stable than $$3d^44s^2$$.

The azimuthal quantum number $$l$$ represents the subshell:

• $$l=0$$ corresponds to the $$s$$ subshell
• $$l=1$$ corresponds to the $$p$$ subshell
• $$l=2$$ corresponds to the $$d$$ subshell
• $$l=3$$ corresponds to the $$f$$ subshell

For $$l=1$$, we count all electrons present in the $$p$$ subshells:

$$2p^6 + 3p^6 = 6 + 6 = 12$$

Therefore, the number of electrons with $$l=1$$ is

$$12$$

For $$l=2$$, we count all electrons present in the $$d$$ subshells:

$$3d^5 = 5$$

Therefore, the number of electrons with $$l=2$$ is

$$5$$

Hence, the number of electrons with azimuthal quantum numbers $$l=1$$ and $$l=2$$ are respectively

$$12 \text{ and } 5$$

Thus, the correct answer is Option (D).