Why do elements with a higher atomic number tend to be more radioactive

this is some information in what I search

Explanation:

Stable atoms have a binding energy that is strong enough to hold the protons and neutrons together. ... All elements with atomic numbers greater than 83 are radioisotopes meaning that these elements have unstable nuclei and are radioactive.

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.