What is the total number of electrons present in completely filled 3s, 3p, and 3d subshell having same value of magnetic quantum number?

Step-by-step solution

For the 3s subshell, l = 0 and m_l = 0 . It contains 1 orbital with 2 electrons. For the 3p subshell, l = 1 and m_l = -1, 0, +1 . It contains 3 orbitals, each with 2 electrons. The number of electrons with m_l = 0 is 2. For the 3d subshell, l = 2 and m_l = -2, -1, 0, +1, +2 . It contains 5 orbitals, each with 2 electrons. The number of electrons with m_l = 0 is 2. The only magnetic quantum number common to all three subshells is m_l = 0 . Total number of electrons having the same magnetic quantum number ( m_l = 0 )