Write a note on hydride compounds of Group-16 elements.

Explanation

All the elements of Group-16 form hydrides of the type `H_2E` (E = O, S, Se, Te, Po)..
Example : `H_2O, H_2S, H_2Se, H_2Tc, H_2Po`. The acidic strength of hydrides increase down the group. This is due to decrease in bond dissociation enthalpy of H-E bond down the group which facilitates the release of proton.
Acidic strength : `H_2Te gt H_2Se gt H_2S gt H_2O` The thermal stability of hydrides decreases down the group due to decrease in bond dissociation enthalpy of E - H bond.
Thermal stability : `H_O gt H_2S gt H_2Se gt H_2Te`.
The hydrides of group-16, except water shows reducing property. The reducing property increases down the group due to decrease in bond dissociation enthalpy of E - H bond.
Reducing strength : `H_2Te gt H_2Se gt H_2S gt H_2O`
The boiling point of `H_2O` is maximum because of intermolecular H-bond. `H_2Te` shows high boiling point due to its large size which results in strong intermolecular forces.
Boiling points :` H_2O gt H_2Te gt H_2Se gt H_2S`.