The order of thermal stability of hydride is :
`H_(2)O gt H_(2)S gt H_(2)Se gt H_(2)Te`
This is related to the bond dissociation enthalpies of the E-H bonds where E stands for the element.
E-H bond : `" " O-H " " S-H " " Se-H " " Te-H`
Bond dissociation enthalpy : `("kJ mol"^(-1)) " " 463 " " 347 " "276 " " 238`
Based on bond dissociation enthalpy, `H_(2)O` is maximum stable thermally while `H_(2)Te` is the least stable.
