Question

Write the order of thermal stability of the hydrides of Group $16$ elements.

Answer 1

Order of thermal stability

Stability of hydrides of group 16 elements decreases as we go down the group, i.e.,
$H_{2}O>H_{2}S>H_{2}Se>H_{2}Te>H_{2}Po$.

This is because down the group, size of the element $\left(E\right)$ increases, $E-H$ bond length increases and thus, bond enthalpy decreases and hence stability of $E-H$ bond decreases