Question

An orbital is described with the help of a wave function. Since many wave functions are possible for an electron, there are many atomic orbitals. When atom is placed in a magnetic field the possible number of orientations for an orbital of azimuthal quantum number 3 is:

• A. Three
• B. Two
• C. Five
• D. Seven

Answer 1

Answer: (D)

Seven

For the azimuthal quantum number, $l=3$

It is a p-orbital.

Magnetic quantum number $m_l$ have values from $-l$ to $+l$ and total of $2l+1$ values.

For $l=3$, $m_l$ values are:

$m_l=-3,-2,-1,0,1,2,3$ for l=3; total $m_l$ values =7= Number of orientations of orbitals.