Chemistry: The Central Science (13th Edition)

The maximum number of electrons that can occupy subshell $4f$ is 14.
*NOTES TO REMEMBER: - The maximum number of electrons which can occupy an orbital is 2. - The number of orbitals in a subshell depends on the type of subshells: +) Subshell $s$: $l=0$, so $m_l=0$. Therefore, 1 orbital. +) Subshell $p$: $l=1$, so $m_l=-1,0,1$. Therefore, 3 orbitals. +) Subshell $d$: $l=2$, so $m_l=-2,-1,0,1,2$. Therefore, 5 orbitals. +) Subshell $f$: $l=3$, so $m_l=-3,-2,-1,0,1,2,3$. Therefore, 7 orbitals. Subshell $4f$ has 7 orbitals. Each orbital can occupy a maximum number of 2 electrons. Therefore, the maximum number of electrons that can occupy subshell $4f$ is 14.