The nucleus of  deuterium consists of 

 

Solution:

Concept: Isotopes are the atoms of the same element, with the same number of protons and electrons but a different number of neutrons  Isotopes of hydrogen are Protium, Deuterium, Tritium 

Deuterium H¹₂ has atomic number 1 and atomic mass 2u, as it has 1 proton and 1 neutron in its nucleus 

Hence, The nucleus of  deuterium consists of 1 proton + 1 neutron