Discuss the electronic configuration of copper.

The electrons identified by quantum numbers $\mathrm{n}$ and $\mathrm{l}$:
$$\begin{gathered} \left(\mathrm{a}\right) \mathrm{n} = 4, \mathrm{l} = 1 \\ \left(\mathrm{b}\right) \mathrm{n} = 4, \mathrm{l} = 0 \\ \left(\mathrm{c}\right) \mathrm{n} = 3, \mathrm{l} = 2 \\ \left(\mathrm{d}\right) \mathrm{n} = 3, \mathrm{l} = 1 \end{gathered}$$

Can be placed in order of increasing energy as:

The quantum numbers listed below are for four different electrons in the same atom. Arrange them in the order of increasing energy. Indicate whether any of the two orbitals have the same energy.

$\left(\mathrm{a}\right) \mathrm{n}=4, \mathrm{l}=0, {\mathrm{m}}_{\mathrm{l}}=0$ and $\mathrm{s}=+\frac{1}{2}$

$\left(\mathrm{b}\right) \mathrm{n}=3, \mathrm{l}=2, {\mathrm{m}}_{\mathrm{l}}=+1$ and $\mathrm{s}=+\frac{1}{2}$

$\left(\mathrm{c}\right) \mathrm{n}=3, \mathrm{l}=2, {\mathrm{m}}_{\mathrm{l}}=-2$ and $\mathrm{s}=-\frac{1}{2}$

$\left(\mathrm{d}\right) \mathrm{n}=3, \mathrm{l}=1, {\mathrm{m}}_{\mathrm{l}}=+1$ and $\mathrm{s}=-\frac{1}{2}$

The two electrons have the following sets of quantum numbers:

$\mathrm{X}: 3, 2, -2, +1/2$

$\mathrm{Y}: 3, 0, 0, +1/2$

What is true for them?