Protium (P), deuterium (D) and tritium (T) are the three isotopes of hydrogen. These isotopes follow the order in different contexts as shown below : T2>D2>P2 [Order of boiling point (BP)] T2>D2>P2 [ Order of bond energy (BE)] T2=D2=P2 [Order of bond length (BL)] T2<D2<P2 [ Order of reactivity with Cl2] Hence, all the given order are correct.