Number of radial nodes, Rn=n−l−1 Number of angular nodes, An=l For 4f-orbital, Principal quantum number, n=4 Azimuthal quantum number, l=3 Thus, Rn=4−3−1=0 An=3‌. ‌ Hence, radial nodes and angular nodes for 4f-orbital are 0 and 3 respectively.