Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R. Assertion A : Isotopes of hydrogen have almost same chemical properties, but difference in their rates of reactions. Reason R: Isotopes of hydrogen have different enthalpy of bond dissociation. In the light of the above statements, choose the most appropriate answer from the options given below:

Step-by-step solution

While isotopes of an element have the same electronic configuration, their chemical properties can differ slightly due to differences in their atomic mass. Isotopes of an element have the same number of protons but varying numbers of neutrons, which affects the overall mass of the atom. The only difference is in their rates of reactions, mainly due to their different enthalpy of bond dissociation.