Write the order of thermal stability of the hydrides of group 16 elements.

Explanation

The thermal stability of hydrides of group 16 elements is directly proportional to the bond dissociation enthalpy of H - E bond. On moving down the group, bond dissociation energy decreases because bond length increases.
Thus, the order of bond dissociation energy is
`H_(2)O gt H_(2)S gt H_(2)Se gt H_(2)Te gt H_(2)Po`
This is also order of thermal stability.