Question

The isotopes of hydrogen have different physical properties due to the difference in mass. They have almost same chemical properties with a difference in their rates of reactions which is mainly due to:

• A. their different enthalpy of bond dissociation
• B. different electronic configurations
• C. different atomic masses
• D. different physical properties

Answer 1

The correct option is A their different enthalpy of bond dissociation

Enthalpy of bond dissociation of deuterium is higher (443.35 kJ $mo{l}^{-1}$) than that of hydrogen (435.88 kJ $mo{l}^{-1}$)