In heavy elements (Z = No. of protons, N = No. of neutrons):

Explanation

The explanation of this is given below: In heavy elements, such as those with higher atomic numbers (larger Z values), the balance between the number of protons (Z) and neutrons (N) in the nucleus can vary widely among different isotopes of the same element. The relationship between Z and N depends on the specific isotope. In some heavy isotopes, Z can indeed be less than N, especially for certain neutron-rich isotopes. These neutron-rich isotopes may be less stable and tend to undergo beta decay, which converts a neutron into a proton, thereby increasing the atomic number. The ratio of protons to neutrons can vary widely depending on the specific isotope and the nuclear forces at play. Some isotopes may have an equal number of protons and neutrons (N = Z), while others may have more protons than neutrons or vice versa. While there are cases where Z is less than N in heavy elements, it's not a universal rule, and the exact values of Z and N will depend on the specific isotope being considered.