Respuesta :

The mass  of  an tom that  contains  28 protons, 28 electrons and  34 neutrons  is 62  amu


Explanation

The mass  of the atom ( mass  number )  is total number  of protons +  total number  of  neutrons.

The units of mass number  is amu ( atomic mass  units)

total number  of protons= 28

total number  of neutrons =34


mass of atoms is therefore =  28 + 34=  62  amu