The element boron (b, atomic number 5 and atomic mass 11) is right above aluminum (al, atomic number 13 and atomic mass 27) in the periodic table. how many more electrons does aluminum have than boron? why? there are 16 more electrons in aluminum because you subtract the atomic mass of boron from aluminum. 27-11=16 there are 8 more electrons in aluminum because you subtract the atomic number of boron from aluminum. 13-5=8 you can't determine how many more electrons aluminum has than boron from this information. there are 14 more electrons in aluminum because you subtract the atomic number of aluminum from its atomic mass. 27-13=14