Given that, electrons and nucleus are at infinite distance, so potential energy of H-atom is taken as zero.Therefore, according to Bohr's model, potential energy of a H-atom with electron in its ground state =−27.2eVAt d=d0​, nucleus-nucleus and electron-electron repulsion is absent:Hence, potential energy will be calculated for 2H atoms =−2×27.2eV=−54.4eVPotential energy of 1 molH atoms in kJ=100054.4×6.02×1023×1.6×10−19​=−5242.4192 kJ/mol