Which is the correct thermal stability order of `H_(2)E(E=O,S,Se,Te` and `Po)`?

Options

A. `H_(2)SeltH_(2)TeltH_(2)PoltH_(2)OltH_(2)S`
B. `H_(2)SltH_(2)OltH_(2)SeltH_(2)TeltH_(2)Po`
C. `H_(2)OltH_(2)SltH_(2)SeltH_(2)TeltH_(2)Po`
D. `H_(2)PoltH_(2)TeltH_(2)SeltH_(2)SltH_(2)O`

Answer

D

Explanation

In oxygen family down the group thermal stability decreases
order of thermal stability
`H_(2)OgtH_(2)SgtH_(2)SegtH_(2)TgtH_(2)Po`]
this is because M-H bond dissociation energy decrease down the group with the increase in the size of central atom.