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Question
Give reasons for the following : H2Te is the strongest reducing agent amongst all the hydrides of Group 16 elements.
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Solution
As the size of the elements increases in the order O < S < Se < Te, the X−H bond strength decreases from H2O to H2Te and therefore, the bond dissociation enthalpy decreases. Hence, due to the increase in the tendency to release proton, the element's reducing tendency also increases. Therefore, H2Te is the strongest reducing agent amongst all the hydrides of Group 16 elements.
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