Question

If an atom of an element has eight electrons in a subshell having five orientations of 4th energy level, write the electronic configuration of the element and four quantum numbers for valence electrons.

Answer 1

1. Identification of the subshell of 4th energy level: d orbital have 5 orientations, hence, 8 electrons resides in $4\mathrm{d}$ subshell.
2. Electronic configuration: The electronic configuration of the element is $1{\mathrm{s}}^2,2{\mathrm{s}}^2,2{\mathrm{p}}^6,3{\mathrm{s}}^2,3{\mathrm{p}}^6,4{\mathrm{s}}^2,3{\mathrm{d}}^{10},4{\mathrm{p}}^6,5{\mathrm{s}}^2,4{\mathrm{d}}^8$.
3. Quantum number for the valence electrons: The valence shell is 4d.

1. Principal quantum number $\left(n\right)=4$
2. Angular momentum quantum number (I) for d subshell is $2.$
3. Magnetic Quantum Number $\left(m_l\right)=$$m_i=-l-0-+l\text{.}$$=-2\text{to}+2\text{i.e. ,}-2,-1,0,1,2\text{.}$
4. Spin Quantum Number $\left(m_s\right):=+$$\frac{1}{2}\text{or}=-\frac{1}{2}\text{.}$