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Chemistry · PYQ NEET UG 2019(1)
हिन्दीWhich is the CORRECT thermal stability order for \( \text{H}_2\text{E} \) (\( \text{E} = \text{O, S, Se, Te and Po} \))?
Correct answer · Option 2
\( \text{H}_2\text{Po} < \text{H}_2\text{Te} < \text{H}_2\text{Se} < \text{H}_2\text{S} < \text{H}_2\text{O} \)
Explanation
Thermal stability decreases down the group as the E-H bond length increases and bond dissociation enthalpy decreases. Therefore, \( \text{H}_2\text{O} \) is most stable and \( \text{H}_2\text{Po} \) is least stable.
