Question

Which of the following hydrides of Group \(16\) elements has highest reducing property?

• A. \(\text{H}_2\text{O}\)
• B. \(\text{H}_2\text{S}\)
• C. \(\text{H}_2\text{Se}\)
• D. \(\text{H}_2\text{Te}\)

Hint:

Going down the group, the H-E bond gets weaker, so the hydride gives up hydrogen more easily.

Answer 1

The Correct Option is D

Step 1: Use bond dissociation energy
The E-H bond energies fall as O, S, Se, Te: roughly $463, 347, 276, 238$ kJ/mol.
The lowest value is for Te.

Step 2: Answer
The easiest hydride to oxidise is the one with the weakest E-H bond, H$_2$Te. Water is the weakest reducer.

Final Answer:
Weakest H-Te bond, so option (D). \[ \boxed{\text{(D)}} \]